I would suggest that if you have to have that stupid penalty, it should be defined as a defender hitting the passer with his helmet or torso after the ball has been thrown. Contact by merely hands and arms would not count, unless the quarterback is thrown to the ground after completing his throwing motion (and with the usual rules about helmets and facemasks). Simulating roughing the passer, or flopping as they seem to call it in foreign devil football, could be penalized with five yard penalty assessed at the end of the play, to keep quartbacks for diving to the turf if they get tagged.