I know of 2 roads (kinda close to each other) where 2 lanes merge into 1 lane. I used to use both roads frequently for my evening commute home. I think 1 may even have a sign telling drivers how to properly use the zipper method. I now avoid both for different reasons like the black plague. The 1 road I always used to avoid Fairfax County "Highway" (Parkway) before the customer moved locations, I was amazed how I never got into accident because almost every day it seemed like I had a near miss. Majority of the time the near misses were due to the car in the left lane that was ending maintaining the same speed until the "end" even though it was at my rear quarter panel and I had to slow down to keep from avoiding running into the cars ahead of me who had slowed down to merge. A few times I had drivers speed up to be along side of me and forced their way over because their lane turned into a left turn lane.

I avoid the other location because there have been too many near misses ahead of me. Plus, the merger is right where people are trying to exit a post office.