Here in Poland it works quite well, at least when the merge is expected.
But we have signs reminding people of that and they also display this kind of driving tips on info boards on motorways when there is nothing more important.
Yeah, that’s the big asterisk on the “zipper merging is more efficient” premise. It assumes that things are already bottlenecked. If you have the space to merge early without slowing down, you do that. People trying to force their way in at the last minute (when they didn’t have to) is one of the things that triggers the bottleneck in the first place.
I’ll merge early but also try to go a bit slower than the person in front of me to open a gap which allows me to absorb some of the traffic wave (where flow alternatively speeds up and slows down from people trying to get up to speed only to have to slam on the brakes because some car ahead wasn’t going fast enough to maintain that), as well as leave space for others to merge at speed.
Though I sometimes close the gap if I notice people pulling into the right lane to try to skip the line.
K but people don’t tend to complain about those driving down the empty lane if there is no bottle neck.
Obviously if you’re racing down to cut someone off, that’s just as rude as any unsafe merge, but thats not unique to zipper merging, so is it relevant?
Zipper merge is always the most efficient if people dont prevent merges, regardless of road conditions. It means both open lanes are used to move cars forward until the last moment when they cannot. “Move over early” means less throughput in the system, no matter “how open” one lane is at some point.
By blocking merges, you causes braking, which is what causes traffic. You framing people driving efficiently to prevent traffic as “people trying to force their way in last minute” means its you creating traffic, not them.
You’re arguing from a sense of moral suppority, I.e “I got in line early, you should have to,” not from a sense of efficently moving cars down a road.
It’s rare, but I think they’re referring to when it’s open enough and running at optimal speeds. It happened the other day on a side street during an off hour, the free lane couldn’t cut to the front without going like 70mph in a 40mph zone.
And it shows exactly what I’m talking about. When people are more interested in filling lanes than merging efficiently when one is disappearing, they reduce the throughput of traffic over all.
At a respectable speed though, merge lane is not a passing lane. My rule is whatever speed can be maintained stay with the car speed in the lane to be merged into, jamming the front punishes everyone cueing properly.
The the merging lane is empty for a half km, then it’s proper to drive to the front and merge. If you just drive slow, then you’re a problem for the sake of being a problem.
Drive to the front, match speed, zipper merge. It isn’t hard.
Depends on what you mean by “the front”. Too many people do not know how to look thousands of feet down the road. Probably why so many merge too early.
The assholes that also do not know how to look thousands of feet down the road fly to the end and cram in, which does nothing but further reduce throughput because it slows the lane people need to merge into.
That is literally what a zipper merge is, and what you are supposed to do. Go to the end and merge. If they are “cramming” in, then the people in the lane are not doing their part either, because you are supposed to let people merge.
When people properly zipper merge, traffic will keep flowing. Your complaint about reducing throughput is a “well of fucking course it will” because you’re putting more cars through the same space regardless of where they merge. People who slow down with hundreds of meters of space, then stop and wait for someone to let them in makes the problem worse, not better.
Literally, no it is not. Nowhere does it say you have to get to the end before merging. THE WHOLE FUCKING POINT is to MATCH TRAFFIC SPEEDS AND MAKE ROOM to reduce interruptions. NOT to fill up all available space where ever you find it.
If you fly to the front past a bunch of stopped cars, you ARE NOT MATCHING SPEEDS. Those assholes are not zipper merging. Period.
The people who merge early are not utilizing all space, but THROUGHPUT IS ABOUT LANES AND SPEED. When one lane is disappearing, you CANNOT MAGICALLY ADD THROUGHPUT by cramming in before the bottleneck. Period. Ever.
Nothing about the zipper merge says, “last minute”. It is wholly and entirely about matching speeds and making room.
Guess what dictates the speed of the lane that gets to travel forward? The amount of traffic that gets to travel… in that reduced number of lanes.
The people racing to the end of the closing lane are doing nothing but increasing traffic density, which directly hurts the effort of zipper merging. If it’s going from two lanes to one, the density MUST halve somewhere if traffic is full. That’s never going to happen at full speed if there are assholes wedging in at the last second and pushing traffic density past what people comfortably go full speed at.
Hint: it is not bumper to bumper on the highway.
Again: Merging at the last second does nothing but push traffic density up. Often past comfortable densities, which will slow traffic. It’s the exact same reason rolling stops happen even without traffic accidents or lane closures in dense traffic.
Last minute is absolutely part of it. Use the available queueing space to keep congestion from spreading. I don’t know where you drive where bumper to bumper didn’t happen, though.
No it is not. Ever. You cannot magically add throughput by cramming in ahead of the bottleneck. That ONLY increases density, which DEMONSTRABLY reduces speeds.
Guess what happens when speed goes down? Throughput also goes down! You cannot magically add throughput by filling space beyond what is reasonable for the speeds you want to go. That’s not how humans work.
Well a closing lane would be marked with an arrow pointing to the lane next to it, and if it’s closed it’s a red X. You merge before the red X. I don’t see a closing lane the same as a closed lane. Maybe it’s a translation thing. And every country is different.
Merging at the last minute is the correct way to do it.
Zipper merge, you fucks!
thank you. the math agrees, too. zipper merges are the way to go!
I would agree with this if literally anyone else knew how to zipper merge
The solution is educating people about zipper merging, not getting angry at those who actually do it.
Here in Poland it works quite well, at least when the merge is expected.
But we have signs reminding people of that and they also display this kind of driving tips on info boards on motorways when there is nothing more important.
We only started seeing signs in my city telling people to zipper merge, but I was never taught it in driver’s ed, and we really should be.
I wish we had better signage here like you have in Poland.
Gave a ride to someone who for one hour kept bitching about drivers who use zipper merge properly. didn’t want to tell him he was wrong.
he was so convinced and fuel by hatred of better drivers.
Depends. If there’s lots of traffic, yes. If it’s sparse enough that you can merge without slowing people down too much, just do it early.
Yeah, that’s the big asterisk on the “zipper merging is more efficient” premise. It assumes that things are already bottlenecked. If you have the space to merge early without slowing down, you do that. People trying to force their way in at the last minute (when they didn’t have to) is one of the things that triggers the bottleneck in the first place.
I’ll merge early but also try to go a bit slower than the person in front of me to open a gap which allows me to absorb some of the traffic wave (where flow alternatively speeds up and slows down from people trying to get up to speed only to have to slam on the brakes because some car ahead wasn’t going fast enough to maintain that), as well as leave space for others to merge at speed.
Though I sometimes close the gap if I notice people pulling into the right lane to try to skip the line.
K but people don’t tend to complain about those driving down the empty lane if there is no bottle neck.
Obviously if you’re racing down to cut someone off, that’s just as rude as any unsafe merge, but thats not unique to zipper merging, so is it relevant?
Zipper merge is always the most efficient if people dont prevent merges, regardless of road conditions. It means both open lanes are used to move cars forward until the last moment when they cannot. “Move over early” means less throughput in the system, no matter “how open” one lane is at some point.
By blocking merges, you causes braking, which is what causes traffic. You framing people driving efficiently to prevent traffic as “people trying to force their way in last minute” means its you creating traffic, not them.
You’re arguing from a sense of moral suppority, I.e “I got in line early, you should have to,” not from a sense of efficently moving cars down a road.
It’s rare, but I think they’re referring to when it’s open enough and running at optimal speeds. It happened the other day on a side street during an off hour, the free lane couldn’t cut to the front without going like 70mph in a 40mph zone.
Of course a muscle car did just that, but still.
No.
Throughput is determined by number of through-lanes and the speed at which traffic is moving. Period. Completely.
Filling the merge lane when traffic is already slow does nothing but drive density up, which slows traffic further.
Sure, YOU might save some time by passing a bunch of cars, but it DOES NOT IMPROVE THROUGHPUT.
Zipper merging is about NOT having an area of abrupt speed change. It is not about using up a lane that is going away. Period. Ever.
It’s the same as an on-ramp: If you’re speeding up just to slam on your brakes to merge, that’s not zipper merging!
Someone made a simulator for these scenarios where you can adjust on driver behaviour and see metrics in what is most efficient.
https://www.traffic-simulation.de/
And it shows exactly what I’m talking about. When people are more interested in filling lanes than merging efficiently when one is disappearing, they reduce the throughput of traffic over all.
At a respectable speed though, merge lane is not a passing lane. My rule is whatever speed can be maintained stay with the car speed in the lane to be merged into, jamming the front punishes everyone cueing properly.
The the merging lane is empty for a half km, then it’s proper to drive to the front and merge. If you just drive slow, then you’re a problem for the sake of being a problem.
Drive to the front, match speed, zipper merge. It isn’t hard.
Depends on what you mean by “the front”. Too many people do not know how to look thousands of feet down the road. Probably why so many merge too early.
The assholes that also do not know how to look thousands of feet down the road fly to the end and cram in, which does nothing but further reduce throughput because it slows the lane people need to merge into.
That is literally what a zipper merge is, and what you are supposed to do. Go to the end and merge. If they are “cramming” in, then the people in the lane are not doing their part either, because you are supposed to let people merge.
When people properly zipper merge, traffic will keep flowing. Your complaint about reducing throughput is a “well of fucking course it will” because you’re putting more cars through the same space regardless of where they merge. People who slow down with hundreds of meters of space, then stop and wait for someone to let them in makes the problem worse, not better.
Literally, no it is not. Nowhere does it say you have to get to the end before merging. THE WHOLE FUCKING POINT is to MATCH TRAFFIC SPEEDS AND MAKE ROOM to reduce interruptions. NOT to fill up all available space where ever you find it.
If you fly to the front past a bunch of stopped cars, you ARE NOT MATCHING SPEEDS. Those assholes are not zipper merging. Period.
The people who merge early are not utilizing all space, but THROUGHPUT IS ABOUT LANES AND SPEED. When one lane is disappearing, you CANNOT MAGICALLY ADD THROUGHPUT by cramming in before the bottleneck. Period. Ever.
That was the respectable speed part. I agree too slow is also an issue.
Fair.
Nothing about the zipper merge says, “last minute”. It is wholly and entirely about matching speeds and making room.
Guess what dictates the speed of the lane that gets to travel forward? The amount of traffic that gets to travel… in that reduced number of lanes.
The people racing to the end of the closing lane are doing nothing but increasing traffic density, which directly hurts the effort of zipper merging. If it’s going from two lanes to one, the density MUST halve somewhere if traffic is full. That’s never going to happen at full speed if there are assholes wedging in at the last second and pushing traffic density past what people comfortably go full speed at.
Hint: it is not bumper to bumper on the highway.
Again: Merging at the last second does nothing but push traffic density up. Often past comfortable densities, which will slow traffic. It’s the exact same reason rolling stops happen even without traffic accidents or lane closures in dense traffic.
Last minute is absolutely part of it. Use the available queueing space to keep congestion from spreading. I don’t know where you drive where bumper to bumper didn’t happen, though.
No it is not. Ever. You cannot magically add throughput by cramming in ahead of the bottleneck. That ONLY increases density, which DEMONSTRABLY reduces speeds.
Guess what happens when speed goes down? Throughput also goes down! You cannot magically add throughput by filling space beyond what is reasonable for the speeds you want to go. That’s not how humans work.
Yes before the lane is closed. They are not doing that.
No. You are explicitly supposed to go to the very end of the closing lane, and then merge, not before it closes.
Well a closing lane would be marked with an arrow pointing to the lane next to it, and if it’s closed it’s a red X. You merge before the red X. I don’t see a closing lane the same as a closed lane. Maybe it’s a translation thing. And every country is different.