Maintaining a safe following distance is incredibly challenging on busy freeways where hard braking is often 'required'. Most people have likely found themselves in this situation: vehicle changes lanes in front of you; you slow down to maintain a safe following distance, another car sees a gap and changes lanes in front of you. Repeat for your entire commute.
Incredibly frustrating, and I've driven all over North America - there's practically no major city where this doesn't happen. If you're not maintaining a safe following distance on city/residential streets, that's a different matter.
I will never understand why this is so rage-inducing for people.
Changing lanes is a necessary part of navigating, even during busy traffic. People on an on-ramp will need to get in front of somebody. People needing to move back to the right because their exist is coming up will need to get in front of somebody.
Your lane is not a birth right. Let people merge.
> you slow down to maintain a safe following distance, another car sees a gap and changes lanes in front of you. Repeat for your entire commute.
This happens because literally everyone is tailgating each other so hard that the gap in front of you is the only gap that exists for people to change lanes to either get on or off the highway.
It's frustrating because someone is taking your safety buffer as their opportunity to travel faster. And it results in you having to travel slower and slower to maintain the gap that is constantly consumed, tragedy of the commons style, by opportunists.
Slow down a bit to create another buffer. You can even do this before they have merged, as part of the bit where you allow them to safely merge.
I think if you reflect a bit you'll find you are being the same kind of person as them, if you are getting angry that you have to slow down and give up space for someone else. I understand some people can be aggressive though, that can be frustrating regardless of the outcome.
I don't think you're understanding. The point is that 20 people in a row will take advantage of your buffer to slow you down again and again and again, which makes you get to your destination later... because they're being selfish to get somewhere faster, and you're not so you get to where you're going slower.
We're not talking about where they're changing lanes to take the next exit. We're talking about where your lane happens to be moving faster, so they merge in front of you in an unsafe way to take advantage of that and just stay there. Why should you be expected to give them space, as you suggest? How is that fair, that they should get to their destination faster instead of you? Do you not see how that's going to rightfully make someone angry? When they should be waiting for a safe space to open up, rather than forcing you to slow down to create one?
I understand perfectly, 20 years driving, I think people just don't like that the safe answer is to be slow. You will not fix others behaviour, so your options are be slow and generous, get out of the chaotic lanes (unless that's all of them), or join them and be aggressive, claim space, be stressed and annoyed your whole trip.
There is no solution to traffic here sorry, this is more about managing your own frustration and expectations when faced with people at their worst, in the worst form of transport.
The total, confirmed, 100% effective solution is to never commute by highway during peak hours, but few get that option.
I object to the "late" argument made by etho's parent. The difference in time to destination will inevitably be dominated by lights, in city travel, not by modest speed differences (say 45 vs 55) on a highway. Being safe & out of the way is the trick! It would be nice if we got rid of left & u turns and build our roads for that!
The subsidies for cars is crazy when you look at it from that perspective. What you need to do is invest a lot of money in areas and systems that can make it better over time. In the end you are going to spend less.
Ehto is correct and this is the way. I'll go further and say that if someone is tailgating you and it's pissing you off, generously let them pass. Literally pull to the side of the road if you must.
The issue is that when you slow down, you’re (a) creating ‘turbulence’ in the traffic flow with increased speed differential between cars and increased lane changes, which increases accident risk for everybody, and (b) it’s not even solving the problem because you still perpetually have some impatient driver wedging themself in directly in front of you, deleting your buffer zone.
It’s safer to drive a little closer, keep up with other traffic and defend what gap you can in front of you.
Agree with your conclusion here, though. The best response is to simply not drive in this kind of traffic.
Hard disagree. It is not safer to ignore your safety buffer. It is certainly not safer to defend your buffer.
If traffic is very busy, the trick is to just accept people will wedge in front of you and keep going slightly smaller each time to increase the buffer again. You might create 'turbulence', which might possibly decrease the safety a bit for all the impatient drivers doing the wedging. But it increases your own safety. And therefore also that of the people following you and your passengers.
I'm also not convinced on the 'turbulence' part. Keeping a buffer smoothes out any sudden speed variations of the people in front of you, which makes the traffic behind you flow better.
And it might maybe feel a lot slower to let a 100 cars go in front of you on your commute, but just driving 99km/h when the person in front of you does 100 is enough to increase your gap and it makes a whopping 1% of difference.
The only thing is: sometimes a road is just too busy and the space for a buffer just isn't there to begin with. At that point the speeds should go down to accommodate the smaller buffers, which is actually what happens here in the netherlands as long as there aren't too many people ignoring the speeds advisory boards above the highway.
> The issue is that when you slow down, you’re (a) creating ‘turbulence’ in the traffic flow with increased speed differential between cars and increased lane changes, which increases accident risk for everybody, and (b) it’s not even solving the problem because you still perpetually have some impatient driver wedging themself in directly in front of you, deleting your buffer zone.
That's very obviously not true. Slowing down always reduces energy in the system and always reduces global turbulence. It's one of the reasons that countries that lower speed limits see journey times reduce.
Is there a statistics name for the last part? I'd like to compare different countries. It's definitely NOT true in Colombia at least, which makes me believe OP more.
We in Colombia had a public service announcement where it showed someone driving really fast (while still respecting semaphores), and another one going with just enough speed. In the end, they both reach the last semaphore almost at the same time and then they part ways. Essentially it shows that driving crazy fast in the city doesn't necessarily gets you faster to your destination.
Now that I'm an adult, I tested it several times, and it matches 90% of my attempts, but that's in the city, with semaphores. No way I'd think letting everybody steal everybody else's buffer would provide for a reduction in journey time, even in highways. You're adding items to a queue, it'll take longer.
Now, it is probably safer, but we can only take so much even if we are not in a rush.
Slowing down on a busy highway does not reduce turbulence at all, it add chaos and unpredictability to the system. Once car suddenly slowing down to create a buffer zone causes the car behind to slow more and more and can often lead to a stop further back. This has been proven time and again on closed loop systems studying highway traffic flow. They are known as "phantom" traffic jams or shockwave traffic jams. Example, https://www.newscientist.com/article/dn13402-shockwave-traff...
> Slowing down on a busy highway does not reduce turbulence at all, it add chaos and unpredictability to the system. Once car suddenly slowing down...
I agree that slowing down "suddenly" causes turbulence. However, slowing down *gradually* allows you to build up a safety buffer which in turn allows you to avoid slowing down suddenly.
Yes, and they are caused by sudden decelerations which are the result of many factors, including driving too fast for the conditions, roadway, and traffic, and tailgating.
> Slowing down on a busy highway does not reduce turbulence at all,
The only thing that reduces global turbulence reliably on any roadway is reducing speed. All the simulations and real-world implementations show this. It's unambiguous and uncontroversial, except that it requires drivers to slow down, which is politically untenable in many jurisdictions.
It is more dangerous to be slow and have people constantly merging in front of you, rather than be slightly faster and not have all the merging. Accidents happen when vehicles are going different speeds, all things equal.
Obviously it is safer to have longer follow distances, all things equal. But you don't accomplish that if you leave a long follow distance that is cut off a few seconds later by another car trying to get ahead. You end up with a constant stream of cars cutting your follow distance to less than what it would have been if you had just stayed slightly closer to the car in front of you.
We don't live in an ideal world, and having a bunch of cars merging in front of you definitely makes you less safe than having a static situation. I try to make sure I can see through/around the car in front of me, so that I have advance notice of what's happening down the road.
American road laws are insane here. The law should be simple; you must be in the outside lane at all times unless you are overtaking, and once you're done overtaking, you should merge back into the outside lane.
As far as I know that’s the law in every state I’ve driven in, but enforcement is pretty much nonexistent. Some states like Texas or Louisiana might have signs reminding people to stay out of the inner lanes except for passing but I’ve never heard of anyone getting a ticket over it. What’s enforcement like in the UK?
That used to be the case in Ireland too, but confusion due to cultural contamination means pretty much everyone moved to numbering lanes (from the "outside"/"slow"/leftmost lane).
When I did my B license test probably about 30 years ago, the Rules of the Road all referenced inside/outside lanes. When I did my CE license last year, it had been updated to only use lanes 1, 2, 3 etc.
Obviously fast and slow are just colloquial terms.
Why? If everyone followed the rules the lanes would segment into slowest on the right, with gradually increasing speed to the left and people moving between the lanes as needed to overtake. It would be far far far better than the chaos of having to move across all the lanes of traffic all the time because there are random campers driving below the speed limit in every single lane.
First, everyone switches right as soon as there's a gap in a righter lane, so lots of unnecessary switching. Second, the right lane is always full making it hard to merge on or off the highway. Third, the leftmost lanes are underutilized when they could be filled with people who have a long way to go until their offramp.
My decades-long impeccable driving record tends to indicate otherwise. I just don't drive as if I lived in the fantasy land where leaving a long follow distance means I have a lot of room in front of me. It doesn't. It means I get cut off, and the follow distance ends up being shorter than it would have been had I just been following at the same distance as all the other cars on the road.
It is possible of course that the highways you drive are just too busy and the max speed is actually set too high for how busy the road is. That happens more than you'd want because lowering the max of a highway is always an unpopular thing to, even if it's needed.
Still, I tend to find that people underestimate the danger of short distances. Often it's just better to accept a 100 cars going in front of you than to shrug off following someone at 1.5 seconds. It can go well for years because crashes are rare, but when you are in a crash you will be royally screwed when you don't have the reaction distance needed.
This assumes that you can actually maintain a 3 second follow distance. On some roads, you simply cannot, and an attempt to maintain such a distance leads to increased danger from all the cars that cut in.
Simply put: follow distance is not a unilateral decision.
If you actually want the safest option then you should merge all the way right and keep slowing down. Noone is going to merge right if they are trying to go faster, they will only do it to get off the offramp. Meaning the gap will reopen as people exit through the offramp or merge left into faster lanes.
If you choose to go in the fastlane in traffic you should understand that it will have people who do not care about the following distance as much and are just trying to go as fast as possible.
I have found that often times in heavy traffic the rightmost lane can be just as fast or actually faster than a middle or left lane.
> Noone is going to merge right if they are trying to go faster
In my experience even cars that are not trying to go faster will happily merge in front of you unsafely all the time, just because they don't understand the concept of a safe distance.
> If you choose to go in the fastlane in traffic you should understand that it will have people who do not care about the following distance as much and are just trying to go as fast as possible.
It's not about choosing to go in the fast lane. It's about the fact that in heavy traffic, you have no idea which lane will be fastest, because they're all heavy and which one is fastest keeps switching.
> I have found that often times in heavy traffic the rightmost lane can be just as fast or actually faster than a middle or left lane.
That's exactly my point. Which is why you can be in the right lane, and tons of people from the slower lane will try to merge in front of you if you're keeping a safe distance from the car in front.
Your advice is staying in the right lane doesn't apply in these situations.
This is a long thread of people talking past each other. The bottom line is simply this: if you want to drive with a larger-than-average following distance (call it whatever you want, a safety buffer, a "proper" following distance, the point is it is a distance less than the average following distance of the other drivers on the road) then you have to accept that you will not be able to drive at the same speed as the other traffic on the road. It's physically impossible. It can be psychologically frustrating because you see all the cars around you moving at X mph but your self-imposed constraints mean you can only make way at (X minus Y) mph. But them's the breaks, no pun intended
> It can be psychologically frustrating because you see all the cars around you moving at X mph but your self-imposed constraints mean you can only make way at (X minus Y) mph.
This is correct, but I get the sense that people overestimate Y.
Let's say you're driving 60 mph and following the "three second rule" which gives you a ~264 foot safety buffer. A driver then cuts into this safety buffer. Let's assume they like to go fast and enter closer to the front of the buffer so they reduce your safety buffer down to two seconds. In response, you gradually rebuild the safety buffer back to three seconds, costing you an extra second. Soon after you rebuild the safety buffer another car cuts in front of you. Let's say this process repeats every mile of your journey, costing you an extra second every time. This results in you traveling slightly over ~59 mph, making Y = ~1 mph.
Compare that to the lifetime odds of dying in a car crash in the U.S. which is roughly 1 in 100. It's hard to eliminate that entirely, but I'm willing to spend an extra ~1s per car that cuts in front of me to reduce it for myself and my passengers.
Not so. Keeping a constant distance from the car ahead means both cars are moving at the same speed. When a jerk cuts in, after a moment all 3 cars will be moving at the same speed.
We are saying the same thing. When a jerk cuts in, drivers readjust their speed to maintain desired following distance. Net effect, slower speed for all but the lead car
If you personally start with that slower speed to begin with (AKA much longer following distance), you don't have to worry about adjusting down
The fastlane is just another name for the leftmost lane, I am not talking about the one moving fastest.
Again we are not talking about the fastest lane here we are talking about the safest as the OP was concerned about following distance.
> That's exactly my point. Which is why you can be in the right lane, and tons of people from the slower lane will try to merge in front of you
If everyone merged right it would not longer be faster but people do not do this. In the right lane you can slow down as much as you want and never cause an issue so you can always make a gap. In any other lane if you slow down more than traffic you cause issues because people will then try and pass you from the right which is dangerous.
You are placing the burden of your forward following gap on the cars around you but that is a terrible way to drive. You need to be in control of yourself when driving, do not trust that someone is going to follow traffic laws, do not trust that they will go whatever way there turn signal says, do not trust that they will look over there shoulder before merging.
If YOU want a following gap then the only possible safe way to do this is to merge all the way right and slow down whenever someone merges in front of you. There is no other way to do it in heavy traffic. And YES you will have to live with the fact that you will be driving slower than the traffic around you. That's the trade you make if you choose to have a large following gap.
You’re the problem because of the way you are thinking. You don’t own the asphalt in front of you. You’re angry because in your mind you do, and you feel righteous about it. That’s why you are casting a moral judgement about them.
The most efficient throughput of the road system is not for people to “politely” queue up for 5 miles. People should be utilizing the rod and merging in an orderly manner. By adopting some arbitrary self imposed practice that is leading to 20 drivers cutting in front of you, are the one creating an unsafe situation.
Correct, but you _need_ the asphalt in front of you for both safe driving and also to avoid cascading hard braking events. I also don't own the asphalt under me or behind me too, so it's kinda a silly statement tbh.
You do, but if you leave so much that 20 cars are pulling in front of you, you’ve either driving too slow or misjudged and left unnecessary space. At 15-20 mph traffic speeds, you need 8-20 feet. Ideally, cars in a multiple lane to one lane exit scenario should be zipper merging when congestion reduces speeds. Engineers model this behavior and try to design roads to encourage it.
If you do that and get angry when people change lanes in front of you, you have consciously or subconsciously decided you own that 20 foot gap. That reaction impairs judgement and causes accidents.
If 20 people take advantage of your buffer, then you are delayed by a distance of 20 vehicle-lengths + 20 follow-distances. This is about 1000 meters, a distance which you can travel in about 45 seconds. So the net effect of all 20 people merging in front of you is less than a minute delay on your trip. Unless there is an almost constant stream of people merging in front of you, this isn't adding up to more than a percentage point of two of your whole trip.
To be completely clear the conversation is entirely not about zipper merging, but about people who are using safety gaps as opportunities for them to traffic weave attaining a faster than average travel speed at the cost of every one else's average travel speed and safety
Nobody is getting screwed. I've been the person making the gap many many times. You just ignore them, it isn't hard - they are way up there and I'm way back here, plenty of space. I just keep on with my business of safely driving. Sure I often wish I could go the speed limit - but in reality I'm going almost as fast as they are so it isn't like a few feet lost costs me anything. Odds are I'll be stopped at a red light and lose a lot more time once I get off the highway.
Besides, there are only a few people who ever merge in front of me (and then those who don't merge block their lane so nobody else can get in).
In high traffic you’re definitely being screwed - both by the continuing lack of a proper safety gap, and by not being able to go a normal speed. Which does add up in many of these situations.
But I guess we should just all self gaslight to feel better about it?
In Bay Area traffic I’d literally be not moving at all for most of the time if I followed you advice, in heavy traffic. That’s the exact situation I’m talking about.
>> It's frustrating because . . .
> Slow down a bit to create another buffer
> I think if you reflect a bit you'll find
The parent post does return to the psycho-emotional layer of the problem but on the whole the exchange brings to mind the "two movies, one screen" model of perennial problems. In many of the comments here some people emphasize the problem in terms of physics and some see the problem in terms of psychology (both have overlap and are valid).
A third perspective may be "game theory." I think the Prisoner's Dilemma [0] could explain some aspects of the physical/mental problem. In the set below, Driver A's strategy isn't dependent on a singular predictable Driver B but all drivers that may perform the role of Driver B during the course of a commute.
Agent Cooperate Defect
Driver A leaves space doesn't
Driver B^n merge stay
Leaving aside all times in which a Driver B must merge, such as lane ending zippers or merging to approach an exit lane, Driver B merges because there is some advantage to being in the lane of Driver A. If Driver A maintains space they will not just lose to one Driver B but to all Driver Bs.
I conjecture that this is a collective action problem and that above a certain traffic saturation point there must be a social taboo against changing lanes.
This is not to claim that individual perspective shifting is not important. I am reminded of Foster Wallace's Kenyon address "This is Water," [1] quoted below. However, the task of changing individual perspectives is vastly higher energy than the creation of a social taboo, which is why purity codes and other social inhibitors are so prevalent.
If I choose to think this way in a store and on the freeway, fine. Lots of us
do. Except thinking this way tends to be so easy and automatic that it
doesn’t have to be a choice. It is my natural default setting. [...]
The thing is that, of course, there are totally different ways to think about
these kinds of situations. [...] [Maybe] the Hummer that just cut me off is
maybe being driven by a father whose little child is hurt or sick in the seat
next to him, and he’s trying to get this kid to the hospital, and he’s in a
bigger, more legitimate hurry than I am: it is actually I who am in HIS way.
No. That happens when people drive too close to each other and brake. Not when you let off the gas slightly to maintain a gap which prevents this exact thing.
The entire reason this happens is because 98% of people are morons who drive up the next guy's ass. If everyone kept a proper distance it wouldn't happen at all.
> someone is taking your safety buffer as their opportunity to travel faster
Nobody is 'taking' something; we're all just sharing the road, and at little cost. People change lanes for many reasons, and sometimes to pass someone else and travel faster. That's what the left lane (if we're talking about the US) is for.
> results in you having to travel slower and slower to maintain the gap that is constantly consumed,
I understand the theory but that hasn't happened in my experience.
And even if five or ten cars got in front of you, how much distance is that? A random Internet site says the average midsize car is 16 feet; add 220 ft safe driving distance at 75 mph (says another random website), so let's say 240 ft per car x 10 cars is 2400 ft. In that extreme circumstance, it will cost you ~30 seconds.
It's self-fulfilling: If you act aggressively toward other drivers, they will respond in kind. If you treat them respectfully and politely, they act the same way toward you. People behave well and kindly, naturally. We are social creatures.
Not to mention if that if somebody needs to come over, the proper thing to do is signal first. Then I'm happy to politely ease off a bit and open more space for them to come over safely.
It's the people who aggressively slide right over just a few feet in front of me (cutting off nearly all of my safety buffer) without so much as a signal that really drive me nuts.
In Austin too, and probably just caused a driver to think the same thing. They were in the left lane on a frontage road which was suddenly turning left even though there was an entire lane opposite the intersection blocked off by those plastic things that seem popular to randomly place in the road these days. I saw them hesitate and figured they wanted to merge right, so i decelerated a bit to add another car length or or so, at maybe 10-15mph. They had plenty of space, flipped on their blinker, and instead of just merging started slowing down, to which I decided I wasn't going to brake more to allow them to block myself and everyone else from rolling through the intersection. They basically stopped in their lane, and beeped as I rolled by, to which someone behind them beeped at them for blocking the lane.
In Austin if you want to merge, decide if you can, blink and then merge.
Don't expect people to stomp on their brakes and stop to let you in, especially if your already traveling slower than the lane you are trying to get into and decide to further slow yourself.
And if you can't merge, deal with it, exit, or miss your exit and go around. Next time you will be more prepared or you will learn how to properly merge.
My experience driving in MA and NY was similar, but so often it was because a rusted out shitbox was trying to merge in that would slow down traffic significantly, and not only put me at risk of rear ending them, but being rear ended myself.
When flows merge, there's turbulence. There's less turbulence if the flows are more closely matched, including speed.
In the UK we are taught that you should not signal until you are ready to manoeuvre. If you follow the rules exactly this can put you in the unfortunate position of being penned in behind shower traffic.
Unless I'm the last car in a line and there's plenty of open space behind me. Then you should just wait until after I've passed before merging, because otherwise you create a little ripple in the flow. A few ripples and you got a wave, and that's how you get traffic.
So for the love of gods, if you're merging, even if you signal, match speeds for merging. If you're too slow to match speed, then suck it up buttercup, and hang out in the right lane until there's an opening.
It seems like a tragedy, but actually it can be a boon as long as you travel in neither the leftmost nor rightmost lane. The majority of the traffic entering your buffer will be exiting your buffer out the other side as soon as they can, so you can just chug along at a (greatly reduced, but) consistent speed. Meanwhile, the traffic to either side of you is in standstill, paralyzed by your bow wake.
It's wild to me how often the left lane is not the fastest lane.
I've had times where the right lane ends up being the fastest. On I-5 near Woodburn, OR, it's 3 lanes. So many drivers, including truckers, will often stay out of the right lane entirely to avoid being caught up in traffic coming on/off. Meanwhile, the left lane is going 5 mph under the limit because there's a left-lane camper somewhere miles ahead. So I can fly past everybody in the right lane because there's actually barely any traffic coming on/off and everybody is avoiding the right lane for no reason at all.
The section of I-5 between Portland and Salem is absolutely psychotic, and I have never been able to reason out exactly why. It consistently has a left lane jammed with angry people going at or below the speed limit, a fairly normal center lane filled with cruisers, and a mostly empty right lane with the occasional big rig and regular very-high-speed cars expressing their frustration with the left lane by going 25+ mph over the limit in the right lane.
I know that's what you basically just said. Just venting. The driver behavior in that section of freeway confounds me, and I do not know what the underlying cause is. It is otherwise an unremarkable bit of interstate like any other.
The alternative is that you're stuck going 10+ mph under the limit because of a left lane hog.
Banning passing on the right only works if keep-right-except-to-pass laws exist and are thoroughly enforced. Most states in the USA don't have keep-right laws, and those that do, it's never enforced, so many people don't even know it's actually the law.
EDIT: US-26 westbound immediately outside downtown Portland is notorious for left lane campers. The limit is 50 mph, but without fail, there's some moron going 40 mph in the left lane. You wanna go slow? Fine, but do it in the right lane where you belong.
AFAIK all US states have some form of "keep right" or "slow poke" laws in various forms that distill down to keep right, except to pass.
So the laws do exist, they just are never enforced. Even when said left lane campers cruise by state patrol, I never see them stopped. Hell, I rarely see them stop people going 15+ over the limit either so not actually sure what they're doing.
Its not against the law in any US state (a quick search seems to back this up) to pass on the right. With one huge gotcha, it must be "safe" defined in various ways.
OTOH, most states have a stay right except to pass, slower traffic keep right laws.
Which means, that unless the person to your right is weaving through traffic, driving on the shoulder, or a few other bits of unsafe behavior, if someone passes you on the right your likely the one violating the law by not moving right when your not actively overtaking/passing someone.
There is not a single state in the USA where using the right lane to pass slower traffic in the left/center lanes is illegal. It is allowed everywhere.
It's not the fastest often because it's oversubscribed and people do not understand that the car has a 3rd, mostly underuntilized, state of neither pedal depressed (ie "coasting") ... so they create cascading braking pileups ...
To be fair, some (automatic) vehicles have such tall gearing that coasting will not slow you down if on a flat, let alone downhill. I've driven a few, and I can't stand them. You have no choice but to tap brakes.
I much prefer cars with short gearing for better engine braking. I continue to choose to drive a manual party for better engine braking.
So many people don't even use regular cruise control. They'll have nobody in front of them for miles and their speed yo-yos between 60 and 65 mph. And if you pass them because your cruise is set at 66 mph, they'll speed up to match, but then eventually decide to pass you, get in front, and slow back down to 60. The only way to end the stupid cycle is to go 70-75 mph until there's at least 1/4 mile between the two of you.
The adaptive cruise control in my Subaru rarely coasts. It isn't smart enough to see a gap slowly narrowing and start coasting, and it isn't confident enough to temporarily allow the gap to be smaller than the setpoint while it coasts to recover the gap. So it brakes and wastes energy, and I don't use it.
Truckers sometimes have a good reason to do that -- they can't brake or accelerate as quickly as a small vehicle, and thus can end up going very slowly if they stick with the right lane. To a driver going 3 exits down the 205 it's not a big deal, to a truck driver doing the same they may be at the end of a long haul up the I5 and every minute starts to count since it can affect their pay. And if you can avoid hard braking/hard acceleration in the right lane, that can help your fuel costs quite a bit since slowly coasting behind someone doing 5 under in the left lane is more efficient than jerking around in the right lane.
There are plenty of ramps on I5 and 205 that I merge to the left for because I know they will spill into the right and (when it exists) middle lanes. Because of how traffic also reacts to brake lights (some people brake too hard even when they have sufficient distance to let off the gas and coast to a slower speed) it seems like it ends up making my experience through those stretches a bit better.
Ultimately, any individual behaviour is largely irrelevant, it's what the whole mass of cars moving along does that affects things the most. Often you don't want to be the (significantly) odd one out regardless of the situation.
That's not a good reason, those truckers are just assholes. I'd like to see the authorities enforce the law and fine them heavily. Put them out of business.
I've done a few tours around the world on the interstate system, so I've seen my fair share of truckers. Yeah, some are assholes, but there are stretches and routes where their behaviour makes sense, even if I don't like it. It's on them for how they behave, but understanding why they behave that way can make it simpler to deal with them in real life. As real, squishy people, not a system of rules.
Would I love to see CHP or OHP fine every left lane trucker in the 'no trucks in left lane' zones? Hell yes, but until that happens, I understand the trucker behaviour.
Being a bit more nuanced, I dont mind a trucker in the left in a 2 lane section (they're likely trying to avoid bad interactions with merging cars from the right) ... but it does bother me when its 3+ .
This is what most frustrates me about driving in Florida. The right lane is nearly always the fast lane, yet is the lane with most 'events.'
When asked, they'll say they feel safer in the left lane because they don't feel safe having to deal with people turning out and merging. So you get instead people driving fast in the lane meant for pulling out and merging.
> as long as you travel in neither the leftmost nor rightmost lane
What I really hate, however, is that plenty of people will cruise in the center lane but still not leave a decent gap between them and the car in front. They effectively turn a three lane freeway into two one-lane freeways by hobbling the ability of anyone else to switch lanes. The freeway moves way smoother when there is a modest, predictable speed differential between each lane so that people can find their way into the next lane over without having to force the issue.
But you’re not getting slower and slower for every car. Lets say 100 cars pull in front of you, and let’s be say each car adds 5 metres of space, so you have 500 metres of ‘lost’ space to regain.
At over 100 km/h that would be ideally 5m for a car and 70m for a safe distance between each one so 7,5km, which is 4.5 minutes at 100 km/h or 9 minutes at 30 mph.
It brings me peace to see other people thinking this way. You should be an active participant on the highway, making decisions to maximize flow. Leaving space so people can merge, controlling speed to smooth slowdowns, anticipating traffic patterns, etc.
All of the people tailgating are contributing to the congestion.
The trick I keep in mind in situations like this is to look at brake lights ahead of me. If cars are braking and I'm accelerating, I'm probably going to end up driving very inefficiently. By letting off the accelerator, I don't close the gap as quickly, and eventually, the turbulence in the traffic flow steadies out. Instead of stopping and starting, I roll at an averaged out speed, which doesn't feel as frustrating (it's kind of relaxing) and is better for fuel economy. There are, of course, the weavers who jump from gap to gap, tailgating and pushing. Sometimes it works, sometimes they just get jammed up.
I don't drive as often as I used to, but on I-76 coming into or out of Philadelphia, traffic gets snarled and becomes stop-and-go. Every now and then, someone next to me appears to have the same understanding of fluid dynamics as I do, and we build up enough of a buffer that we are able to eliminate the stop-and-go, even if it means rolling at 5mph with a big gap between us and the cars in front of us.
There's no good way to communicate what we're doing, even to each other. But I like to think that when this happens, it has a positive effect that ripples out for miles.
> I roll at an averaged out speed, which doesn't feel as frustrating (it's kind of relaxing) and is better for fuel economy
Yup. The brake pedal is an evil device that converts cash into brake dust and waste heat. Before I got an EV, I always drove in such a way to use the pedal as little as possible. As a result, in my previous car that was stickered at 24 mpg city/30 mpg highway, I averaged 32 mpg. I don't even drive slow, I just drive smoothly. If your average speed is going to be 5 mph, then you'll get much better economy driving a constant 5 mph than your speed being a sine wave between 0 and 10 mph.
Good driving instructors make you aware of that early on, at least mine did.
I'm not saying that I'm a good driver, because I make mistakes like any other driver out-there, it's just that I oftentimes go with the "maximize the flow" thing instead of just following my individual "well-being" as a driver as a result of what my driver instructor told me some years ago.
> I will never understand why this is so rage-inducing for people.
The train of tought goes something like this. You want to get to your destination quickly as just like everyone else and are doing everything correctly, but the assholes exploit that safety distance as a gap available for them to switch into and repeatedly forcing you to break to maintain a safe distance. Oh and the even less rational people think everyone overtaking them has stolen their rat race position.
Leaving a keeping a safe distance feels unsafe since other drivers will squeeze into it. Subjectively it feels safer to close the distance, but the numbers don't lie. Tailgating kills.
> I will never understand why this is so rage-inducing for people
Putting my armchair psychoanalyst hat on: I think American society embeds a need to be the "winner", and are you winning if end up behind another driver who's contending for "your" spot?
If you've driven elsewhere for a while, you start noticing subtle driver differences, such as drivers who want to merge into your (slower) lane never braking to merge behind you and always accelerating to do so, even when you're at the tail end of a vehicle chain in your lane.
Driving in Melbourne -- I won't generalise to the wider Australia -- is often much the same.
Comparing to the experience of being a passenger on a bike in Saigon, the level of cooperation there is way higher, possibly due to a sort of necessity.
I had this feeling while observing traffic there, that, while the latency and throughput of the roads during high traffic times are still kinda awful, at least for bikes there's a slow continuous progress that simply wouldn't exist without cooperation.
Funnily enough, my experience driving in Los Angeles was distinctly not terrible. Traffic was usually good enough to drive in, though there was very little regard for the speed limit on the freeways! I suspect I may have just been lucky to miss the worst of the traffic.
I'll tell you what I specifically and intentionally do when I need to change lanes. I brake slightly, signal, and wait for the person on my right or my left to pull ahead of me, then change lanes immediately _behind_ them. Then sit there for a moment until my following distance evens out a bit.
This ensures that
a) I do not cut anyone off accidentally, and minimize the amount of stress in my immediate part of the universe
b) I will (most likely) have plenty of room behind me after I change lanes, reducing chances of anyone else running up on me
c) If there's noticeable traffic, the time I spend signaling and waiting for the person to move slightly ahead of me gives plenty of warning to the people _behind_ them that I'm about to enter the lane.
Ultimately, yes, of course in principle you're right, when I change lanes, I enter the lane in front of someone.... but I _can_ control whether I enter as far as possible ahead of them.
You shouldn't be braking when changing lanes is what I was taught, you should be matching the speed of the lane you're merging to. There are many drivers who think that braking is always the right solution, when sometimes it's a little more gas.
And in inclement conditions, it can make the difference between losing control of your vehicle or not. When you brake, you decrease your steering ability in most cars. Fine when its calm and sunny in CA, not so much when it's icing over near Ashland OR on the pass.
Well, sure - braking is mostly relevant when merging to the slower lane, when merging to faster lane I generally do not need to - since that lane is already moving faster, just need to speed up slightly and time it for the right moment.
My point is, it feels safer and easier to aim to enter a new lane with the aim of "following" someone, rather than trying to rush in "ahead" of someone. But maybe it's just me.
It's considerate communication. Lurching into the next lane .08 seconds after the blinker first flashes says things like "Your life isn't worth the basic consideration and respect of communicating my intentions" and scales up to "I'll communicate, but you're not worth any sort of common courtesy" - that can be upsetting to people.
It doesn't even have to be real. There's huge room for miscommunication. Unpredictable movements and perceived aggression, or unwillingness to be considerate to other drivers on the road, there's a whole wealth of information being processed, regardless of how little is actually real.
Now add the total lack of accountability for the driver's emotional state (don't you love yelling at other drivers, completely free of judgement?), and you can see how things spiral into road rage so relatively easily, even if everyone involved is normally a pretty chill, rational person.
If you're tailgating or brake-checking, or being inattentive and sloppy, you're basically threatening people's lives with a few tons of high speed metal, even if you don't intend that at all.
Ideally, the rules of the road are meant to reinforce a mutual understanding of the game being played. Behavior occurring when expected, proper signaling, observing limits, and making the effort to communicate where possible is a signal that you and the other driver are both operating by the same set of rules, giving you both confidence that neither of you are going to be a danger.
I've seen little "cute" exceptions where locals develop a subculture of dangerous assumptions and then get aggravated when someone from out of town doesn't immediately get it. There are other areas where aggression and what amounts to flagrant disrespect are the norm, so you've always gotta be adaptive, but ideally you get people conspicuously following the same set of rules as a sort of game theoretic optimal strategy for driving.
It's frustrating when it eats into your safe following distance. The driver merging in ahead of you is being dangerous and not leaving a safe following distance for themselves (or you).
Might depend on your location, but usually you are legally required to allow a merge. Which makes sense, the system stops working when two lanes that are required to merge, don't merge because people are being petty and entitled.
Yes. If people are constantly moving into your appropriate head way this is doubtless annoying but the correct response is allow yourself to decelerate slowly to re-open that space again, repeat as many times as necessary, even if it means a bunch of agros end up in front of you. Better for them to be in front where you can see them, than behind or to the side, were you can't.
Yah. There's something that feels unjust about it -- the perception that the people cutting are getting something over on you -- that causes us to want to behave badly.
But even if 2 dozen people go around you and creep into that following space, you've been cost like 45 seconds at worst. Better not to play the game.
Also, it really doesn't happen that often. I'm that guy following at 3 or 4 car lengths in rush hour traffic and people aren't constantly funneling in front of me. It's a hypothetical "problem" that is bigger in your head than in reality.
Sometimes I think it's just people's reflexive scarcity mindset that tells them "that spot must not be that desirable or someone would be in it."
Regarding the broader topic of hitting your brakes, I find that I can commute 20 miles in stop and go traffic and only tap my brakes a couple of times. Helps to pace yourself behind the car 3 cars ahead of you instead of the guy right in front of you.
I'm that guy following at 3 or 4 car lengths in heavy traffic an people are constantly funneling in front of me, all to go exactly the same speed they'd be going if they were behind me.
We'd also avoid a lot of accidents if we stopped the people that are doing lane changes for position-jockeying and no other purpose.
So it's bad to be mad while driving, but there's a lot of lane changes that deserve the ire. (It's a tiny fraction of drivers that get really bad, but a less tiny fraction of lane changes.)
Being angry at them won't change their behaviour, but will make you more stressed. Remember: driving like that is its own punishment, because they'll be extremely angry and frustrated at everything. Between that and the realisation that driving 2% slower adds about 1 minute more per hour of driving you have to do, I find I can avoid stressing at people lane weaving and have a nicer journey myself.
> Being angry at them won't change their behaviour
Yes, but the comment above was about society collectively making a decision, so that's the context I responded in.
And while it's relaxing to not worry about your own exact speed, I don't see how that lets you avoid stressing about the people that are lane-weaving. They're acting dangerously and I need to be ready to react to them.
Unless they careened into your vehicle while making the lane change, just calmly allow your vehicle to drift away from theirs until you have a safe buffer again, and take joy in the fact that it didn’t meaningfully impact your arrival time, but you’ve meaningfully impacted the safety of your immediate surroundings.
I try to maintain a constant speed in traffic, even if other people are speeding up and slamming on the brakes around me. Something like the average speed of traffic. Slamming on the pedals isn’t going to get you there faster.
Even if I do need to brake, speeding up more slowly also usually means I have more buffer time to slow down too.
This algorithm is garbage because it puts no value upon the danger cause by other traffic changing lanes when they would not have otherwise.
You're just going to wind up being approximately the slowest person on the road, which is fine if you're constantly trying to go slower to build space but this means that a bunch of traffic that would have not gone around you will do so. This ups the danger vs a steady flow less all these lane changes because every "thing" other people do is an opportunity to do it badly.
Kinda ironic when you consider that TFA was about detecting dangerous merge situations in the data.
Absolutely agree. I take it a step (probably too far) further and think if you’re breaking on the motorway at all, you’re a bad driver. Ok, sometimes you have to, it’s chaotic out there, I get it. If you’re paying attention to actually driving your two ton killing machine you can drive for 200 miles on a motorway and not touch the break once.
I just had to hard brake a few days ago. A driver a couple lanes over on 101 slammed on their breaks, rotated 90 degrees, and came to rest across a couple lanes (one of which was mine). Fortunately, I was alert, driving the speed limit, and in the right-most lane, with nobody following me close. The whole thing happened in less than 5 seconds.
Or stuck on a highway with bad drivers. My local paper's current "bleeds => leads" story is about a head-on highway crash, between a big pickup truck and a wrong-way driver. Less that 4 hours after being posted, that story has already slipped off the front page.
I'm not sure the article, the article being off the front page now, or driving with bad drivers has anything to do with it.
The article stuff definitely doesn't.
Driving with bad drivers should incentivize you to follow less closely and require less hard braking, not more.
There's a motte where some poor fellow is always maintaining the car-length-for-every-10-mph rule and yet keeps being passed inside that distance by innumerable bad drivers the fellow is surrounded by.
I pity that fellow.
He has an excuse.
He also isn't observably real in any of my 21 years of driving in Buffalo, Boston, and Los Angeles.
I feel harsh for saying this, I am only saying it because A) this subthread is specifically about there isn't an excuse B) this stuff involves our lives. Thus, this is an appropriate venue because the people in the venue know what to expect, and poking at someone's thoughts on it may help them immeasurably.
It doesn't normally require hard braking, but when automated emergency braking decides to slam on the brakes at random for no reason in my own car, everybody behind me will share my resulting insurance rate increase.
It's almost as if the purpose of the system is what it does.
If you think people are going to cut in front of you, provide a safety cushion large enough to account for that. Aggressive drivers almost universally will consume the forward part of the space cushion you leave. At most you will simply need to lift the accelerator to maintain space. The only time someone cutting in front of you should require hard braking is if they also brake hard.
It does require patience to do this, because all aggressive drivers will use the space you provide. But ultimately the travel time difference in flowing traffic is negligible.
I'm not sure it's that negligible. Mythbusters found that weaving in and out of traffic could save between 5 and twenty-five percent. Now A) Mythbusters did an experiment with an N of like 4 or something, along a single commute in the Bay Area, so it's basically anecdote and I'd love a better source if one existed, but it is at the very least proof-by-existence that larger impacts on travel time _can_ happen. And their non-weaving person was, if I recall from the video, not constantly decelerating to keep a buffer.
And from personal experience in some places, keeping such a buffer, in some traffic conditions would just literally be impossible. There are sometimes enough aggressive drivers such that they can just consume it faster than one would be able to create it. It is simply not always the case that you have sole power to create and keep the recommended buffer size (although very often it is and you can).
I keep a decent buffer whenever I am able, but at some point, you have to bow to road conditions.
Letting a large fraction of the freeway cut in front of you will turn normal drivers behind you aggressive, or at least aggressive enough to go around you. There's a balance to be struck.
In your haste to be snide and look down your nose what you've ignored is that this interaction is not "free".
Traffic moving with an approximately constant following distance is safer than traffic where one element is constantly traveling under speed to build up a following distance and is slowly filtering to the back as traffic comes upon and then moves around it. If the lane people are pulling into for passing is traveling substantially faster than the traffic that is being queued up behind to be passed then some amount of the people pulling out to pass are necessarily going to do so aggressively or within thinner than "perfect world" margins.
Every thing drivers on the road must perform carries some inherent risk. That a bunch of traffic that would have not gone around you will have done so means that many otherwise unnecessary merges or lane changes and then lane changes back will have happened. Each one of these represents an opportunity for things to go wrong above whatever the baseline is.
What I am saying is not groundbreaking or rocket science and the fact that I have to spell it out in detail to an adversarial audience speaks volumes about this audience and the volumes it speaks are not positive.
The premise of this line of comments is that the other drivers are acting aggressively. Whatever you're picturing in your head is a different situation from what everyone else is talking about.
Tailgating is against the law. Tailgating causes hard braking.
I recently pulled my travel trailer from OK to Charleston, SC and back. I never drive over 65 MPH for safety and MPG reasons. I always stay in the right hand, slow lane except if I have to take a left lane exit. Since I was always driving slower then everyone else, not once did I have to hard brake. Tailgating is a choice and a dangerous one.
I was never honked at, even by the crazy semi truck drivers.
>I was never honked at, even by the crazy semi truck drivers.
Because you were towing a camper and "slow and in the right lane" fits people's mental model of how recreational/nonprofessional heavy traffic or otherwise "handicapped" vehicles ought to behave.
When you have problems is when you behave to a standard beneath what other people expect from whatever kind of traffic you are.
In the Atlanta area I've experienced a few times people FLYING up on me in the right hand lane while I'm cruising along at a conservative, gas sipping 55 MPH in my old truck, blaring their horn at me like I'm some kind of maniac.
Driving and living in Atlanta after living in Charleston and Raleigh felt like transitioning from a modern cooperative society to an island of cannibals. The amount of aggression needed to change lanes largely regardless of attempts to signal good faith and politeness is baffling. Driving is a fascinating ritual with vastly differing norms across regions. It would be interesting to learn if anthropologists have studied this
> Driving is a fascinating ritual with vastly differing norms across regions. It would be interesting to learn if anthropologists have studied this
And Psychologists!
Reading the comments in this thread is quite amusing.
As a driver in India, i can tell you anything goes as long as you don't get into an accident (which may/may-not kill you) or get caught by the police.
No rules matter and the only goal is to "one-up" everybody else on the road and if they are trying to "one-up" you, then prevent it by any means possible. It is a "game of chicken" in its purest form; game theory in action. Rules are mere suggestions only followed by the meek and the weak.
You have no idea how invigorating it is to drive in India.
I don't mind that sort of traffic, as long as I'm in Somebody Else's Car or an old junker that's already banged up. In these situations, the biggest and ugliest car/truck with the meanest driver always wins.
Drive in India and you will understand mathematical concepts of Chance/Randomness/Probability/Non-determinism/Game Theory/etc. along with philosophical concepts of Fate/Destiny/Providence/etc. in so direct and visceral a manner that you will never forget the lessons. Sissified countries with rules and regulations for driving can never give you such direct knowledge.
The game of chicken models two drivers, both headed for a single-lane bridge from opposite directions. The first to swerve away yields the bridge to the other. If neither player swerves, the result is a costly deadlock in the middle of the bridge or a potentially fatal head-on collision. It is presumed that the best thing for each driver is to stay straight while the other swerves (since the other is the "chicken" while a crash is avoided). Additionally, a crash is presumed to be the worst outcome for both players. This yields a situation where each player, in attempting to secure their best outcome, risks the worst.
How to learn One-upmanship/Gamesmanship:
The British author Stephen Potter actually wrote a manual on the practice of such games titled The Theory and Practice of Gamesmanship (or the Art of Winning Games without Actually Cheating) which sissies can study to become strong - https://en.wikipedia.org/wiki/Gamesmanship
For the even more sissified sissies who do not want to read a book, there is a documentary titled School for Scoundrels Or How to Win without Actually Cheating) which is very instructive - https://en.wikipedia.org/wiki/School_for_Scoundrels_(1960_fi...
Disclaimer: I am not responsible for the consequences if the above emboldens you to act in such a manner in your specific context.
That's easy to deal with: They're behind you. Ignore them.
Setting the side mirrors based on the AAA method works for a lot of reasons, and it helps with this too. So does flipping the center mirror over to the dark side.
Out of sight, out of mind.
They can be elect to stay back there behaving however they want, or they can go around be however they need to be somewhere else.
If you just can't stand it anymore, then just hop off the highway. It can be a good opportunity to stop for some coffee or a soda. Or, you know: Just to get out of the car, stretch out the ol' legs, and taste that acrid city air, think about something or someone in the world that is beautiful for you, and chill down a second.
Or just go up one exit ramp and down the entrance ramp on the other side of the crossroad, if the intersection design allows this move to be made safely and conveniently.
They almost certainly won't follow. They'll instead be disappearing down the highway at warp speed the whole time you're doing this, and you'll probably never across them again in your entire life.
It only costs a few minutes. They may seem interminable, but they're few. The benefit is relief from the mounting agony of dealing with this aggressive driver that might otherwise stick with you the rest of the day and that's good for your brain health.
(And if they do follow after you give them every opportunity to not do that? It's not Hollywood or the national news and this actually doesn't happen much in the real world on an individual level, but: Call the police at 911 or 999 or 0118 999 881 999 119 725 3 or whatever it is, and get some help.)
> Sounds like pretty extreme, weird behavior that you are advocating.
Advice for when someone is following closely in anger that summarizes to "try getting off the highway for a minute and if that fails call the cops." is suggesting you perform "extreme, weird behavior"? I don't understand your reaction at all.
The people in question weren't angrily following me. If that were the case, there's no need for any theatrics.
The first weapon to be employed is a Middle Finger. If that proves ineffective, it's followed by a lugnut taken from a coffee can that I keep handy. If and when things get to that level, the person usually wises up quick and finds a new hobby. There are other tools available if the nutcase decides to escalate further.
No, in this case it was just people speeding along at 95 (in a 70) who were terribly offended at my dangerously slow driving, who wished to register their indignation as they flew by, momentarily held back but undeterred as they sped off to their Bright New Tomorrow. Message received, loud and clear.
Escalation usually doesn't improve things, including for the person displaying the universal finger (or throwing the lug nut).
You've got a choice: You can keep plodding along in your truck while you escalate and retaliate and get all grumpy and stuff, or just keep plodding along in your truck without any of that noise.
The errant, instigating driver won't really learn anything either way.
> The first weapon to be employed is a Middle Finger. If that proves ineffective, it's followed by a lugnut taken from a coffee can that I keep handy. If and when things get to that level, the person usually wises up quick and finds a new hobby. There are other tools available if the nutcase decides to escalate further.
I, uh, okay but I hope you realize that this is far more extreme than what the other person was suggesting!
Are you kidding? Driving all over Creation trying to shake some crazy off my tail, getting on/off the interstate, calling the cops ("please sir, drive across town to handle my problem for me!"), and so on is what you consider normal, acceptable way of Handling Business, but simply throwing a lug nut at the son of a bitch is too much? Really strange culture you've got there.
That one's easy: leave space in front of you for those merging onto the highway.
So much of road etiquette boils down to leaving adequate space so others can maneuver around you. Trying to optimize your travel by destroying any gaps as soon as they appear actually has the opposite effect.
It's really not. I drive at an upper-percentile pace, so I am rarely dawdling along in the right lane.
However, on the rare occasion I've found myself going slowly in the right lane, it's stunning how incompetent most people are at merging. It's like they don't even consider looking for an opening in traffic, matching the freeway speed, etc. They just lumber in front of you at 43mph, and maybe, if you're lucky, look in their mirrors after they've already caused you to slow for them.
Very true and it's the reason I will always leave several car gaps in front of me in heavy traffic. Just because I have electric brakes on my travel trailer, it doesn't mean I can slow down normally, they just assist. Most people really don't think about that, of course, so they ignore the trailer and just weave in and out.
Speed is a very dangerous thing when pulling any type of trailer and it always amazes me when I see a truck pulling one at break neck speeds and somehow thinking they can maneuver normally when someone causes a situation where they have to make a split second decision.
This is accurate in many ways.
I use the auto cruise feature on my car frequently and I notice several things happen unless I set the distance as close as possible (which I don’t like to do. ).
1. In any amount of traffic above “a few cars” people will cut in front of me, sometimes two, negating the safe following distance. Regardless of speed.
2. If I have a safe following distance while waiting for someone to get over. (I e they’re going 60, I want to go 70), if I have my distance set at a safe following distance, people are much more likely to weave / pass on the right.
(My theory would be that the distance I’m behind the person in front of them signals that I’m not going to accelerate / pass when the person gets over ).
Disclaimer: I don’t usually have to drive in any significant traffic, and when I do (Philly, New York City), I’m probably less likely to use the automatic features because the appropriate follow distance seems to increase the rage of drivers around me.
I always wonder why so many people observe this when I never have. It makes no sense logically; it's the speed of the car in front of you that determines whether they should switch lanes, not the size of the gap behind it. There is no reason for them to cut in when your lane is no faster. Perhaps you are just the sole person leaving enough room for people to execute needed lane changes.
At any rate, even if people are continuously going around you like water going around a rock in a stream, you only have to drive 2 mph slower than traffic to constantly rebuild your following distance from the infinite stream of cutoffs. But my experience is the majority of following distance is eaten up by people randomly slowing down, not cutting in.
In the auto cruise example, it’s leaving perhaps 2 - 2.5 car distances. In close traffic the average human I would bet is leaving 1 or less then 1.
The issue is not that I can’t rebuild the following distance, the point I’m trying to make is that even if I constantly rebuild the following distance it sets off a cascading effect.
I’m following at set speed, car cuts in front, hits brakes, I now slow down, car behind me slows down, I rebuild following distance and car perhaps 7-8-9 cars behind me repeats because at some point the cascade magnifies to a larger slowdown behind.
Can I mitigate this by manually letting my distance be closer for a time, and slowly easing to larger ? Yes.
But if I allow the car to do it automatically, it will increase the follow distance at a rate that causes a cascade in tight traffic.
Though - I do think with these discussions on HN- it does depend on where you’re driving.
My experiences are centered on East Coast, thinking of route 80, 81, 83, etc. or Philly / New York City.
The driving experience is radically different in California, Florida , or the mid west.
I would say when driving in California people seem to navigate traffic better. (SF, LA) then on drivers on 80/81/83.
(Or perhaps it’s due to better designed roads ).
> In the auto cruise example, it’s leaving perhaps 2 - 2.5 car distances. In close traffic the average human I would bet is leaving 1 or less then 1.
At 60 kph (16.7 m/s) 1 car distance (about 5 m) is less than one third of a second. Even 2.5 car lengths is less than a second. I use traffic aware cruise control on my Tesla set to the maximum separation which is about three seconds, so 50 m at 60 kph.
Three seconds separation is in fact the recommended following separation in most European countries and in Germany in particular 0.9 seconds or less can result in a hefty fine, see https://en.wikipedia.org/wiki/Two-second_rule
In the UK some stretches of motorway have chevrons marked on the road indicating the required spacing at the speed limit.
I do drive in the slow lane frequently - and this still occurs. (My go to is to set my cruise 6-9 mph over the speed limit, if passing to smoothly pass and get back over, and spend as much time as possible in the slow lane. )
However - I will say most of the roads I’m on are 2 lanes of traffic. I will have to experiment and see if this doesn’t occur when there are 3 or 4 lanes.
The idea of cruising 15km/h over the limit is absolutely crazy to me. That will get you 3 points and a minimum $500 fine here. We have "average speed zones" too!
Where I live travelling at that speed will get you passed by every cop and state trooper driving on the same road. A lot comes down to local norms and enforcement.
Apologies - you’re correct. I should have been more specific in that I was referencing the scenario of:
I’m car 2, waiting to pass car 1. (Who’s passing a car slowly ). I have safe following distance.
Car 3, passes me in the right lane, and then either follows car 1 closely, or, quickly passes them on the right. (Usually as they’re in the process of moving over, causing them to then swerve back).
I realize I communicated this in an absolutely abysmal fashion.
In Southern California the "fast lane" is the medium speed lane, and the "slow lane" is the actual fast lane. It's where people tend to weave in and out of traffic at 15-25 mph speed differentials.
I don't know you can find that traffic always bunches up. And if one is content to sit in the gaps in between, almost never anybody cuts in. I drove twice 1000 mile trips each way last year and it kind of worked. It's more of a mindset than anything else. Fastlane is not that fast or it would be empty, lol.
I'm one of the faster drivers and I maintain a safe distance. (I usually have the most distance in rush hour.) It's very easy with adaptive cruise control or the other self-driving technologies that are on the market.
The only people who cut too close to me are driving recklessly.
That being said: If you're in the mode where people are constantly changing lanes in front of you, think a bit about how you're driving: On the freeway you're supposed to stay to the right except to pass, and you're expected to keep up with the flow of traffic. Are you going slow in the left lane? Are you driving too slow? Are you camping in the right lane by a busy interchange?
> and you're expected to keep up with the flow of traffic.
This is very state dependent, if we are talking about legality.
In WA state, for example, there is no "flow of traffic" law or similar. The limit is the limit, and any excess of the speed limit is illegal regardless of what all other drivers are doing. So even if the right/slow lane is going 100MPH through the 70MPH zone, you are legally expected to still go 70.
Thankfully we do have laws against left lane camping, but I rarely see it enforced.
You’re confused. If you know of ANY US state that has a flow of traffic law that allows cars to exceed the speed limit so long as they are keeping up with other traffic, I’d love to see a link to their traffic codes. Speeding doesn’t suddenly become legal because two or more drivers do it together.
This has nothing to do with the expectation that slower traffic stay in the rightmost lanes, which is what GP is addressing.
> Speeding doesn’t suddenly become legal because two or more drivers do it together.
That's not true. Examples:
I once pulled out my local newspaper where local judges were petitioning to have speed limits raised because they were throwing out speeding tickets due to excessive fines. This was in Massachusetts, in the late 1990s or early 2000s, about a road in Shrewsbury near lake Quinsigamond. The context was that the speed limit was 25, traffic flowed at 40-45, and they would throw out tickets for people doing 50.
I was once pulled over in a Massachusetts tollbooth even though I was the slowest driver on the road. (2004, I90 westbound at the intersection of 128, when EZ Pass still had to go through actual tollbooths.) If I was given an actual ticket, I would have point-blank told the judge that I was going half the speed of everyone else and feared getting rear-ended; then the case would have been dismissed. (The cop also knew this, because he recognized me from traffic court and knew that I'd make him look like a fool for pulling over the slowest driver.)
In my place, there's a significant group of drivers who will ride your tail too close hoping you'll move over so they can get 1 car ahead. And if they see more than 0.9 car length in front of you they will do what they can (weaving other lanes) to try and get into that space, 1 car ahead of you.
As far as I can tell it's pure selfishness and competitiveness. Their desire isn't to cooperate and arrive it's to take from others for their own gain.
Also "Only pass in the left lane" only makes sense when the lanes aren't significantly full. The guy in the left lane wants to do 90mph but the average speed of traffic is <55mph. Should I move over just because I'm doing 55 (despite wanting to do 65) and they want to do 90? They can only do 90 if there's a cascading group of drivers in front of them who defer their own desires to the desire of the most aggressive. Seems obvious to me that moving over to let them pass is not the right move.
Having driven all over NA, and Europe, I find it more prevalent in NA. Less distance, more people in large pickups throwing their weight around to make someone move out of the way.
And a design of giant freeway interchanges that require shifting lanes.
E.g. on the 405 in CA. 7 lines going South from the Valley towards Santa Monica.
That's 7 lanes you need to cross if you're in the HOV lane.
Honestly imo the driving license requirements and the respective fines for violations is too low. Rigid rules generally improve the traffic flow. But as soon as someone just doesnt care, the system breaks down.
I live in a place that has harsh winter conditions with ice, gravel and the occasional loose tire stud flying into people's windshields, warranting frequent expensive replacements.
Somebody on the radio said that "just set the adaptive cruise control to max distance and your windshield will last way longer". It does feel overprotective at times, especially in slow and dense traffic, but I think there's a nice point in general.
Another trick that works is just to let the windshield get cracked once. Then it will be immune to further rock strikes. Studies have shown that freshly replaced windshields are 937% more likely to be hit with a rock.
Does it really matter though? Is the end result just a couple of minutes later in a 30 minute commute? Or does it actually make a large difference in travel time?
> Is the end result just a couple of minutes later in a 30 minute commute?
More like a few seconds.
Every car that merges in front of you only costs you their following distance. If the average following distance is 1 second, then you are simply 1 second slower than you'd have otherwise been. So unless this is happening continuously every 30 seconds on your 30 minute commute, you will lose less than a minute.
The "but if I kept reasonable following distance, people will keep merging in front of me and I'll lose time" excuse is pretty thin given this analysis.
And an insurance claim can easily eat 40 hours of time between the insurance companies, other lawyers, buying a new car, medical appointments and recovery. That's 19,200 minutes you won't get back, or about 52 years of driving 1 minute slower each day.
It doesn’t - but people don’t necessarily make rational choices regarding speed and driving. There’s a tendency to de personalize other drivers.
A slight increase in average speed really only makes a significant difference over long drives. (5 mph increase over a 10 hour drive can cut off 50 minutes).
Otherwise we are talking about small differences in efficiency.
(I would be very open to another opinion here.).
My opinions are formed by nearly ~2 million miles driven at this point, two different driving courses, and the motorcycle safety course.
One thing I truly think that’s overlooked is how reduced road noise in the vehicle cabin can both reduce driver fatigue, but also frustration in traffic.
> A slight increase in average speed really only makes a significant difference over long drives.
Yes! I feel like I can't shout this loud enough. In addition to maintaining a safe driving distance, just leave a little earlier. The stuff I've seen people do in order to save 20 seconds boggles the mind.
Unfortunately, I think commuters fall into a gamification mindset. They're trying to set a new lap record each day, and you can see the results just by driving (or walking) during rush hour...
> (5 mph increase over a 10 hour drive can cut off 50 minutes)
You can't really say that without knowing the starting speed, or alternatively the distance. All you can say is that a 5 mph increase over a 10 hour drive with get you 50 miles farther.
I would argue I can still say it /can/ cut off 50 minutes.
If you do a comparison of a 600 mile trip at 60 vs 55 you’re pretty close.
But yes, to be pedantic and more exact, you are spot on that it will get you 50 miles closer.
But in real world examples,
If you’re traveling 700 miles.
65 vs 70, 70 will reduce your time by 43 minutes.
So in certain scenarios, 5 mph difference must be able to save you 50 minutes ! ;)
(I do understand your point, and you’re correct. I’m just poking fun at it- my point with the mph difference is because 50 miles doesn’t have the same translation for most people at 50 minutes, but is a more accurate data approach. )
I have been doing the same commute at the same time for the better part of a decade. At this point I can look at my watch and tell if I'm ahead of schedule or behind schedule and infer what the compounding effect will be later in my commute.
I can easily shave 10% off my commute by lane changing to avoid the lanes where turn lane traffic tends to back up into the travel lanes, ramp traffic and "problem people".
I test the null hypothesis several times a month by carrying bulky topheavy cargo that precludes a bunch of lane changing without more effort than I want to put in.
I don't think there's much to be gained by simply lane changing to chase fleeting gaps in traffic. The wins and losses will probably mostly cancel out.
It used to be more of an issue when I was younger. Now that I'm older and more 'seasoned' (plus reflexes do slow down), I'm far more patient and have no issue maintaining a healthy following distance. I think the statistics reflect this in age vs. accident rate as well.
Unfortunately, sometimes over a 45 minute freeway commute, dropping back repeatedly means arriving 15 minutes or more later. Again, no big deal now, but it was somehow unacceptable when I was younger.
For your commute to take 4/3 the time, you would have to be averaging 3/4 the speed -- going 45 in a 60. That doesn't make sense because even going 55 would mean traffic pulled away from you rather than you having to drop back from it. Going 55/60ths the speed means you arrive in 60/55ths the time, or an extra 4 minutes on a 45 minute commute.
This was part of the training materials of one bus driver I knew. When people continually take that gap and you continually have to back off, it only adds a negligible amount of time to the commute.
Okay I'm thinking of a very Shenzen kind of gizmo for your car that projects a bright red laser "keep out" box on the road in front of your car which is adjusted in size for your current speed.
We have something like that in eu with road markings. Both for clear weather and fog/rain. They mark some of the lines differently, and tell you how many lines you should have between you and the car in front. I think they were first trialed and then printed in several places.
There's a couple of bits of motorway in England with that, I'm pretty sure the M6 and the M1. There are white chevrons painted on the road and you keep two of them between you and the car in front.
Also "Keep Two Chevrons Apart" is going to be the name of my specialist Citroën breaker's yard.
Cool. But I'm thinking this box floats in front of your car on the road in real time. See you're driving and ahead of you on the road is this box. At night it might interfere with your night vision, might have to workshop that a bit.
I think a lot of people would just consider that a challenge.
On the occasion when I am towing our travel trailer, it is really incredible how unsafe that makes other drivers act around me. They will jam themselves in front of me at all costs, with no consideration for physics.
I see this happen to semi trucks on the highway. People interpret big open space as a place to merge. As you say, people have no consideration for why there might be a large space in front of a semi. A 50k lb+ truck hitting the back of a ~4k lb vehicle is not pretty.
Can't wait to get blinded by lasers when cars are going over bumps and speed humps.
I know you were probably writing tongue in cheek, but that is one of those "solutions" that doesn't stop bad actors and makes good actors more miserable than usual.
Like LED headlights :-). It would kind of be a concern except that geometry in in your favor. The angle down they would have to shine + the size related to speed would result in the lasers pretty much always hitting the street except perhaps if you were at the top of Gough[1].
> Maintaining a safe following distance is incredibly challenging on busy freeways
I just put adaptive cruise control on max distance and call it a day, gives me 4/5s to react, and also it starts beeping hard if intervention is required.
Why does this require "hard" braking? If another car cuts in front of you just decelerate gently. You don't brake and wait until the gap is big enough (also if this is stop-and-go traffic, you should be trying to avoid braking at all)
My original observation wasn't worded as well as it could have been. I meant in situations where hard braking could be required on a moment's notice for no particular reason (e.g. Chicago freeways where everyone is doing 70 mph bumper-to-bumper and decreases to 10 mph all of a sudden).
Indeed, when someone changes lanes in front of me, I gently let off the accelerator, but as someone else noticed, that can enrage drivers behind me (I don't take it personally), and I'm definitely traveling fast enough to remain in the middle lanes.
Maintaining a following distance is going to be one of the things that improves dramatically once self driving cars are widespread. Self-driving cars simply don't care that someone cut them off, they'll just happily open up extra space again and again.
You don't need self driving, just traffic aware cruise control. Pretty much every modern car can have this as most now come with automatic emergency breaking and the same sensors can be used.
People only take your lane if you are in the fastest lane. If you are in any slower lane, people tend to jump in and then leave and I have no problem with people who do that.
You can also keep a gap in the fastest lane but you need to keep track of other cars on the road. You’ll observe that most cars rarely leave their lane. People who tend to leave their lane keep smaller gaps in front of them. Use that knowledge. There are many more factors than just that but if you start observing everyone drive, your little simulation in your head will start putting other drivers into buckets.
These comments make me grateful that we have the concept of 'lane discipline' in the UK. It's rare to see the 'fastest' lane be anything other than the outside one. Otherwise we keep left and out of the way.
I leave a lot of distance, but people rarely change lanes to get in front of me, because the person I'm following isn't going any faster; the separation is in d not v. Most people who do change in front of me are there only briefly on their way to an exit, which means I'm increasing the fluidity of the traffic flow, so I'm happy about that. If I didn't leave space, they'd likely hard-brake in front of someone, causing a slowdown.
> another car sees a gap and changes lanes in front of you
Usually if you maintain the slightly slower speed you had to maintain a safe following distance it doesn't matter, as the distance will either increase or they'll leave for another lane. You have to get used to drivers doing messy things in front of you, but at a safe distance. When doing this you are in fact helping the traffic becoming more fluid.
I had a slow realization that I could just let people jump in. My goal is to maintain a constant speed and never have to hit the brakes, and I can usually still do that regardless of whether people jump line.
But yes, the principle of it is incredibly aggravating ("that space is for safety, not YOU, green Acura!!!") but I actually kinda like the practice of trying to be zen about it. I mostly get through a long trip at the same rate :)
Woah, like, "green Acura"? Where are you driving that you ever see one of those? In the USA?
I looked up an image catalog, and it seems that if an Acura's going to be green, it is likely to be an NS-X, which are fairly exotic as Acuras go.
I owned a black Integra for a while. If any had been green in those days, I would've definitely noticed! And, I definitely would've yielded the right-of-way to them, just so I could gawk and stare!
This almost always happens when you are in the passing lane, and you are not passing. It’s much more rare in the right lane. Mythbusters, and also other traffic studies, show that returning to the right lane on the freeway whenever possible adds almost no time to a trip.
> another car sees a gap and changes lanes in front of you.
it's largely a problem in the left lanes, thats where drivers will bunch up most. the subjective feeling is mostly a reptile brain issue though, the feeling you're getting done over. driving is 90% id, sadly.
The most frustrated people are those behind you, and if I was id soon be another person merging in front of you. If people are constantly merging in front of you, either everyone is going too fast or you are going too slow :)
I admit that I probably don't leave as much space as recommended, but I leave a good amount of space to never need to hard brake, and people don't keep moving in front of me either.
> vehicle changes lanes in front of you; you slow down to maintain a safe following distance, another car sees a gap and changes lanes in front of you. Repeat for your entire commute.
For the sake of argument, assume you follow the "three second rule" and that the other driver is slightly aggressive and enters closer to the front of your safety buffer. You are now down to a two second safety buffer so rebuilding it back to three seconds costs you an extra second of travel time.
In practice this happens to me about a dozen times a day. It sometimes feels frustrating, as if each of these drivers is stealing another second I could have been playing with my kids! But ultimately it's worth spending the extra seconds to slightly increase the odds that I arrive home each day to play with them at all.
False. I've done it many times - when you open up space two cars jump in, but the rest don't and so the space remains. But you notice those two cars and think it means more than it does.
> puts you (and the cars behind you) in a less-safe situation than if you followed more closely.
Really? All you have to do is lift your right foot very gently until you have the expected spacing again, no need to sudden changes of speed and if you have traffic aware cruise control it will be done for you. My old Tesla S does it pretty well. I keep it set to three second spacing and when someone cuts in front my car just gently slows down until the spacing is correct again; it doesn't brake unless the car that cuts in is very close.
I do keep three seconds separation most of the time. If possible I engage traffic aware cruise control set to maximum separation for just that purpose. People do cut in but not often; what would be the point of cutting in between two vehicles that are both going slower than your desired speed?
Also perhaps I should have made it clear that I am in Europe where one is expected and required to drive in the outermost (rightmost except in UK and Ireland) lane unless overtaking so the only time anyone would 'cut in' between my car and the one in front is when they are entering a motorway.
I find that respect for safe following distance varies quite a lot amongst the places I've driven.
E.g.
- Switzerland and (somewhat surprisingly) UK: pretty good, people doing idiotic shit is rare enough that I'll usually comment on it if there's another person is in the car. If someone is riding my ass I'll make the effort to try and shake them off.
- Italy and Spain: horrifying, impossible to relax at all on the highway, having someone 2 car lengths off your rear bumper is the default condition.
- France and USA: somewhere in the middle where there are a lot of idiots but they are still the minority.
Subjectively, the USA feels much more sketchy because the rules are so much looser around overtaking.
Incredibly frustrating, and I've driven all over North America - there's practically no major city where this doesn't happen. If you're not maintaining a safe following distance on city/residential streets, that's a different matter.