I drive mostly in D because for me its a real Jekyll and Hyde thing. When I go to sport mode I can't help mashing the throttle and driving pretty much like an ass.
Not sure where you got the idea that driving in sport mode is easy on the tranny, its the opposite. In sport mode you shift at a higher RPM and the shifts are quicker which add more stress to the tranny.
I do some times drive in manual and start from 3rd and just use the 3 gears in hopes of getting better gas mileage, but ususally Mr. Hyde shows up.
