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.
Comment on That's a no
DScratch@sh.itjust.works 3 weeks ago
Merging at the last minute is the correct way to do it.
Zipper merge, you fucks!
Mongostein@lemmy.ca 3 weeks ago
IrateAnteater@sh.itjust.works 3 weeks ago
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.
rainwall@piefed.social 3 weeks ago
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.
taiyang@lemmy.world 3 weeks ago
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.
LurkingLuddite@piefed.social 3 weeks ago
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!
ericwdhs@discuss.online 2 weeks ago
Agreed on never being the one blocking merges, but for the merging party, “if people don’t prevent merges” is such a huge caveat that I think attempting a zipper merge at a lane ending at any appreciable speed is impractical at best and downright dangerous at worst.
If everyone is traveling slow already, failing to merge quickly at the lane ending isn’t a huge threat to safety and just a slight hit to efficiency. Most merges I’ve experienced are probably in the 40 to 80 mph range though. In that case, you absolutely do want to take the first decent merging opportunity you can, because waiting to do it until the lane ending can have huge safety and/or efficiency consequences if another good merging opportunity doesn’t open up at speed.
Also, I’m pretty sure zipper merging was mentioned zero times in driving lessons and tests where I’m from, so you should basically just assume other drivers don’t even have it as a concept. If you’re from somewhere where more people practice it regularly, then I can see why you are more encouraged to enforce it as a baseline.
Starik@lemmy.world 2 weeks ago
This will only be done right by AI.
Banana@sh.itjust.works 3 weeks ago
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?
Buddahriffic@lemmy.world 3 weeks ago
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.
TheJesusaurus@piefed.ca 2 weeks ago
If it’s that sparse then the situation in the meme is a non-issue
Mongostein@lemmy.ca 2 weeks ago
…until people make it an issue by speeding up and cutting people off, causing it to bottleneck
TheJesusaurus@piefed.ca 2 weeks ago
Correct
Semi_Hemi_Demigod@lemmy.world 3 weeks ago
I would agree with this if literally anyone else knew how to zipper merge
Banana@sh.itjust.works 3 weeks ago
The solution is educating people about zipper merging, not getting angry at those who actually do it.
los0220@lemmy.world 3 weeks ago
Banana@sh.itjust.works 3 weeks ago
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.
Philote@lemmy.ml 3 weeks ago
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.
ragepaw@lemmy.ca 3 weeks ago
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.
LurkingLuddite@piefed.social 3 weeks ago
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.
ragepaw@lemmy.ca 3 weeks ago
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.
Philote@lemmy.ml 3 weeks ago
That was the respectable speed part. I agree too slow is also an issue.
ragepaw@lemmy.ca 3 weeks ago
Fair.
IAmNorRealTakeYourMeds@lemmy.world 3 weeks ago
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.
LurkingLuddite@piefed.social 3 weeks ago
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.
Randelung@lemmy.world 3 weeks ago
Last minute is absolutely part of it. Use the available queueing space to keep congestion from spreading.
LurkingLuddite@piefed.social 3 weeks ago
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.
Randelung@lemmy.world 3 weeks ago
It’s not about throughout. You want previous intersections and ramps to be free. The extra lane is car storage space. If one lane is stopped and the other is free you absolutely move up to the merge point. Safely, mind you. The speed limit is way too fast, 30-40 kph is enough. Merging early causes shockwaves that turn into full blown stops upstream. Plus you block the whole lane until you’ve merged.
I’ve done traffic control systems for almost a decade so I actually know a little about the subject.
wonderingwanderer@sopuli.xyz 3 weeks ago
Zooming to the front to try to merge at the last minute and creating a choke point that stops traffic for half a mile is NOT the correct way to do a zipper merge…
DScratch@sh.itjust.works 2 weeks ago
You shouldn’t be able to, because both lanes are full and moving at half speed.
boonhet@sopuli.xyz 2 weeks ago
But they’re not. Zipper merges might be the efficient thing to do, but here everyone is taught to merge early so the guy doing 70 km/h in the empty lane when the speed limit is 50 and then demanding to merge is generally seen as an asshole by everyone else, especially because those people usually don’t wait for you to make room either, they often just start merging into other cars knowing someone will hit the brakes.
wonderingwanderer@sopuli.xyz 2 weeks ago
Except people do it anyway, I’m surprised so many people are trying to pretend they’ve never seen this.
Traffic isn’t some collective consciousness thing that moves like a well-oiled machine. People are selfish and do what they think is to their best advantage, even if it causes the overall traffic conditions to be worse.
Visstix@lemmy.world 3 weeks ago
Yes before the lane is closed. They are not doing that.
MSBBritain@lemmy.world 3 weeks ago
No. You are explicitly supposed to go to the very end of the closing lane, and then merge, not before it closes.
Visstix@lemmy.world 3 weeks ago
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.
flandish@lemmy.world 3 weeks ago
thank you. the math agrees, too. zipper merges are the way to go!