Totally cool with weakened off hand passing, but 2K might be thinking it's confusing because you don't actively choose which hand to pass with, where as you dribble left when you're dribbling left, and layups depend on how you attack (can we still choose left vs right layups like years past with Pro Stick?).
Right vs left passes happen based on situation and positon of passer and receiver, and usually all the attention is focused on the target not which animation might play out. So 2k is wary of having ratings for things that a user doesn't think about naturally, where as in real life you feel and know your off hand weakness when passing.
I think it should be implemented anyway. Bad passers tend to have a bigger fall-off with their weak hand, and good passers tend to be more ambidextrous. It'll distinguish good vs bad passers even more.