I live in Nor Cal. I love being able to split lanes. Especially when traffic is stopped. This way I am not waiting behind a car at a red light while I am looking in the rear view mirror while some moron cage driver is not paying attention and yapping on their cell phone...just before they rear end me!
Now I have gone through the LA area once or twice on my bike....man splitting lanes down there is a scarry deal! My hats off to the people who do that down there.
Unfortunately for us bikers there are a lot of guys who just go about lane splitting the wrong way and "pee" off the cagers. Which in turn seems to make them a little more aware of us bikes in a bad way.
One thing I can pass on to others who lane split...try to be the 1st guy splitting not the guy in the rear!
Ride safe!