TheOak

Leading with the crown of the helmet should not be legal. Leading with the crown is very bad form and taught against at all levels of the game.

When you lead with the crown it changes the mechanics of the impact and the force. When a player leads with their facemask the impact is softened through the mechanics.. the head goes back and the body tends to upright, When a player leads with the crown it is essentially a spearing move and there is no "give". This has absolutely nothing with lowering the shoulder, and a player that does it is not very bright as once the crown is lowered he can not see where he is going or what he is hitting.

When a defender lowers to make a tackle and the RB lowers but leads with the facemask there is a deflection from facemask to facemask contact. When the RB lowers his crown he tends to put his helmet on the chin of the defender.

Strief is correct and on point, and the rule is justified.

Enforcement of the rule is an entirely different conversation.