Interesting post epically for this board. The fact is, it is legal to split lanes in a motorcycle in California is because the motorcycle are "air-cooled" vehicles. To prevent the motorcycles from over heating and cause traffic jams, a law was passed to allowing motorcycles to split lanes in a slow moving and/or a stopped traffic condition.
So, on the same school of thought, and since we can't split lanes. I think we "air-cooled" Porsche and VW drivers should able to use the carpool lanes anytime we want here in CA. Call me crazy, but I think this is a very logical idea.
Paul