I don't get the assertions about contorting fingers on a mouse + keyboard setup.
The majority of PC games out there use maybe 5-6 keys, positioned so you barely have to move your hand. Mouse usually just the left and right click. The nature of the mouse resting on a surface means that aiming tends to be very precise.
MMOs are perhaps an exception, because most have dozens of commands plus the need to type communications to other players. Then again console controllers have difficulty with this as well.
-k