Dont you have probs in the city if you pass through the jamming cars? ( mirror-slalom). Or is it not allowed, to overtake when cars are waiting at a traffic-light?
The laws about "lane splitting" can be different for each state, in the United States country. The state of California passed AB-51 bill, and now it is legal to do lane splitting.
In the state of Colorado, I think it is not legal to be lane splitting, but you can ride next to another motorcycle in the same lane of traffic.