I often see them blocking the left lane waiting to try get into the right one that’s backed up, thus backing up the left lane too and raising the risk of accidents. Not sure how that becomes more efficient, especially as they often try merge after the painted barrier/island when it actually becomes dangerous. Maybe freeway-specific or dependent on number of lanes etc.
Agreed. But that ONLY works if everyone is on the same page. And if like a zipper, each takes a turn consecutively. Even the article mentions: "Like all well-intentioned systems, though, the effective zipper merge requires that all drivers are on the same page, and when’s the last time that happened? We’ll see if this efficient, safe merging technique can find a place in our traffic habits, or, as Minnesota Radio’s Bob Collins suggests, “The zipper merge is going to be this century’s conversion to the metric system in the '70s. Great idea, made perfect sense, and was dead on arrival.”
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The zipper merge works with the understanding everyone is following the rules so the 2 lanes merging always stay at equal lengths
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Sounds great in theory…
It seems to work well where people have been educated on the rules and then follow them - not so much in the south.
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Friend’s husband was having a root canal a few years ago. She was with him and they asked her to come back to see if she could rouse him. She is prone to panic but she took one look and screamed ‘Call 911’ and they did. He was in the hospital for about 10 days I think.
You can bet they take his blood pressure before anything now!
(it wasn’t at his regular dentist, and now that dentist doesn’t let anyone, even her hygienist, work on him. Dentist does it all)
I’ve had two great dentists retire. They were both younger than me!
I do tell the new ones from the get-go that I’ve left practices in the past that recommended aggressive treatment or unnecessary add-ons.
Hey!! I resemble that remark! 
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Well, I implicated myself as well 
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The blood pressure measurement at the dental office does not bother me (minimal time or any other issue, no charges seen on the bill or insurance coverage, and more likely to downsell than upsell), but the upselling issue seems to be common. Here is an older thread on the upselling problem: Dentist buys practice from retiring dentist and finds...
It also assumes driving cooperatively, not competitively. In a merge situation, cooperative drivers in each lane pre-position themselves next to gaps in the other lane so that they can merge easily when they reach the merge point. But competitive driving seems to be common enough, where drivers will try to get past one more vehicle in the other lane, so that the merge tends to result in emergency braking to avoid crashes and results in traffic jams.
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Zipper merge works great when the merging line is not too short or not too long. It has to be just he right length to force people to follow the rule even if they are not aware of it
So, maybe just don’t put up a “merge” notice. Simply let that lane come to a stop - people back far enough will think “accident” or “construction” and won’t know which lane is closed so they will just get in the shortest one. Or put up a “merge ahead, go to shortest lane” sign with no indication which lane will be closed
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Or simply, “Zipper Merge Ahead.”
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I do the zipper merge when I’m in the letting in lane - I’ll hold back to let one car in (but only one). But I rarely encounter anyone who does it when I’m the one in the needing to be let in lane.
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Its annoying when other cars try to get in when you are letting the one car in to alternate, and more annoying is when some clown flies up the lane that is ending knowing that it is ending, and then expects to be let in ahead of everyone else.
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But that driver is doing it correctly, that’s the way zipper merging works — one-to-one interleaving at the merge. When lanes reduce (to any number), all drivers remain in their lanes right up to merge with interleaving at the merge. This is not about politeness or rudeness; it’s about physics. And in some states, it’s the law. You can get a ticket for not allowing the car next to you to merge in no matter how “short” that lane is. It’s everyone “merging” blocks (or miles) ahead of the final lane that causes the slowdown.
I’m gobsmacked by how many drivers did not learn this in driver’s ed. My LEO brother has given out many tickets to drivers who try to crowd out cars that are correctly attempting to interleave at the merge because of their misunderstanding of how this traffic rule works.
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My issue is not lanes ending and merging. It’s when a line has built up for an off ramp and people fly past the line and push in at the last second, both causing a backup in the lane they’re in (which is NOT ending) and making people in the lane for the off ramp slam on brakes.
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I’m amazed how many people walk with traffic and bikers riding against traffic.
Did they not go to safety city? Or had kindergarteners who did?
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Agree, but an off-ramp is not lane reduction. An off-ramp is a single lane reserved for exiting the highway while the lane directly next to it is expected to continue past at highway speed. Annoying (and dangerous), but different example.
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