Splitting lanes is legal in California, so thats what I do. Besides I think people take the whole "bikes are vehicles" or whatever way to far. The basic truth is bikes are not cars. Thus there are special sections in the law for them, such as "ride as far to the right as practical", etc. So seating in traffic behind a line of cars inhaling all the crap seems like a pointless thing to do, and frankly more dangerous because you now run a risk of being rear ended by someone who is not paying attention.