I had the good fortune to do a three month internship in Seattle last spring. And I have to say - after growing up in Dallas, now living in Florida, and seeing traffic in other places... Seattle drivers are unique.

I've seen this [appear to] work in Seattle. While I was there, I tried it, and it appeared to work.

However, while I lived in Dallas, I was aware of this idea, and tried it there - and no way. People cut in, people tailgated - it completely doesn't work.

So I think it partially depends on the nature of the city's drivers. And there is something special about Seattle.