The new NFL rule that bans a player from lowering his head to make contact with his helmet is going to be a mess. There will be plays on which a linebacker, say, instinctively will do what he has always done. That’s to bring his opponent down. There won’t always be time, not on the fly, to adjust and raise his head.
The league is still figuring out how to apply the rule. The penalty will be 15 yards. If the penalty is egregious, as it now stands, officials can kick the player out of the game.