The only thing I can think that the rule would be okay is if they focus on spearing only. However, it's the fine line of a guy lowering his helmet to take an indirect hit, looking to the side at the last minute. The problem is that those are bang-bang plays where the refs are a. often not in the best position and b. probably without realizing it, making the call just before it happens. The league says it will focus on the hits that are legal, but I just don't see it as doable with the speed at which the game is played.