I think one thing is true of any car company- they are in business to make a profit. If for some reason an item is not necessary for the car to function they would not put it on if it costs more money IE the two piece drive shaft is probably more expensive than a one piece. Perhaps though, a one piece by virtue of the increased length would be more expensive than a two peice due to better materials/precision balance requirements. Unless we could talk to the engineer that worked on this part of the drive train every thing is just a guess. It would rock if some of these engineers would post here, they could clear up a lot of issues (yeh, we did this this way because of this). A switch to a one piece drive shaft could be the greatest thing or a complete waste. When someone does it and tells us about it then we will know. That is the greatest thing about these forums, every one can learn from a few people who have taken the, if you will, first step!