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.

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.

…until people make it an issue by speeding up and cutting people off, causing it to bottleneck

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.

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.

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.

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 was the respectable speed part. I agree too slow is also an issue.

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.