On the zipper merge | Ted Sanders
The zipper merge (or late merge) is so misunderstood. The point of the zipper merge is not to increase throughput. The point of the zipper merge is to increase safety (by limiting speeds) and feelings of fairness (by limiting the ability to cut). If you speed down an empty lane to cut in at the end, you are not properly executing a zipper merge - in fact, you are in fact contravening the principles that favor it.
In my view, the best way to execute a zipper merge is to match the speed of the other lane (regardless of whether there is space ahead of you) and then merge at the end of your lane. This procedure is safest and fairest. I want more people to do it.
Spend enough time on the internet, and you are bound to encounter a smug proponent of the zipper merge (also called the late merge).
Springing forth like Batman to the bat signal, at any complaint of a cutting driver, the zipper merge proponent interrupts with smug condescension, in words likely not far from these:
