What are the Pros and Cons of Commuter Lanes?

Question

I have traveled all over the world and lived in Japan, Korea, Germany and now Italy and I am from the U.S.. Nowhere have I ever lived besides the U.S. is there commuter lanes. If you want to cut down on traffic, first built a mass transit system and then charge tolls for the freeways to cut down on people that want to not use the mass transit and so you have enough money to properly maintain them. A compination of these ideas works all over the world. Why is it that people in the U.S. cannot figure this out. It is so simple.

Answer 1

They are the dumbest idea. Rt-91 out of L.A.  added two lanes in each direction. When the lanes are needed , they carry two extra lanes in the direction needed, and two lanes waste. If the road had been designed to carry the four extra lanes in the needed direction at the times needed, the traffic would flow a lot smoother.

Answer 2

Pros-saves times

Cons-whats the matter with crossing the yellow line?