The rule works in soccer. It's better to have it black and white. Otherwise mentors would find a way around it. Both teams would be treated the same.I agree will rule out the tactical stoppages in games.
However if there is visible strike/contact on head and players takes off helmet as play continues or if player has lower or upper body injury, keeps helmet on and physio/doctor runs on (if safe ball at other end of pitch etc), player is treated the player should not be put at a disadvantage.