One respondent said the best argument against the zipper merge in the United States was that too many dangerous fools carried pistols and were willing to use them.

I posted a description of the zipper merge in a Facebook auto enthusiast group, along with a video illustrating the technique, and asked for public comments.

The Texas Transportation Institute found that a zipper merge strategy delayed the onset of congestion at the merge point by about 14 minutes and cut the maximum line of cars by 1,800 feet.

In 2020, Illinois mandated that its Rules of the Road handbook include the zipper merge.

The North Carolina House passed a bill that would mandate the zipper merge when lanes merged into one.