The main advantage to rotating tires was to swap the fronts for the rears. Most people tend to chew up their rear tires a bit more than their front ones if they spin them alot. Of course this can't be done since BMW puts larger tires on the rear of the vehicle. Also switching driver/passenger wouldn't do much for people who turn just as much left as they do right, as most of us do. I also have read that radial belted tires shouldn't have their direction of rotation switched. This of course would happen if you switched the side of the vehicle the wheel was mounted on.