Originally Posted by prathmann

It really doesn't matter how big the metropolitan area population is since traffic safety only depends on the other traffic in your immediate vicinity. Busy intersections in Boise look and operate just the same as busy intersections in NYC, SF, or Toronto. And there's hardly much need for a "cultural shift" since the 'Idaho rules' are already being practiced by a majority of cyclists with regard to Stop signs and by a substantial portion with regard to traffic lights as well. The only difference is that motorists would no longer have a legitimate reason to get mad at such cyclists and the cyclists could stop worrying about getting traffic tickets (i.e. could focus more on traffic dangers and less on looking around for police officers).

As to why the 'Idaho rules' haven't been widely adopted I'd guess it's mainly that bicyclists are such a small proportion of the traffic mix that there's no great political motivation to cater to law changes that only benefit a tiny minority - especially when you already have quite a few motorists who feel bicyclists are 'getting away with something' by not being subject to licensing/registration laws. Just because something is a good idea and would be beneficial doesn't mean it'll be enacted into law unless there's a strong political pressure pushing for it.