Someone from the RMV.... Sounds like the Leominster RMV!

Agreed. Not all driving schools do it because the RMV doesn't require it, but the school I work for does.

I know exactly what and where you are referencing here. When traffic is stopped on the highway, doing a "zipper" merge is really the best way to keep the traffic moving- both the traffic already on the highway and the traffic trying to enter the highway from the ramp. Yes, the merging traffic from the ramp is required to yield- but in a practical sense, the traffic from the ramp would never move if every car on that ramp just yielded stopped and waited. All it takes is one or two aggressive drivers to gum up the works. It's all about being predictable... and aggressive drivers are not.

I'm a driver's ed instructor in Mass. When merging on highway, I tell them to get up to highway speed by the top of the ramp, check mirrors, and signal onto the highway, only stopping for a hazard or stopped traffic. They are instructed to yield to traffic on the highway, but adjust speed and find a gap to slide into the travel lanes of the highway. Some students hesitate and stop or slow down and you are right, it causes other problems.