MINNESOTA NICE AND THE ZIPPER MERGE. When a driver knows that his lane is going to end, but waits until the last possible moment to change lanes, it is called a “zipper merge”. I posted here in 2014 that Washington had joined Minnesota as two states that recommend the zipper merge. It cuts congestion by an estimated 40% and, because everybody is moving at the same speed, reduces crashes.
It turns out that despite the efforts of their Department of Transportation, the zipper merge is still being resisted in Minnesota. This article by Aarian Marshall in Wired entitled “Nice Minnesotans Don’t Get the Cruelly Efficient Zipper Merge” describes how guilt feelings are limiting the use of the zipper merge. A small survey found that 49 percent of Minnesotans were at least “somewhat uncomfortable” zipper merging. One driver is quoted: “Maybe it just feels wrong? I feel guilty about passing all those people and merging at the end.”