Derrick Henry is often praised for his use of the stiff arm. But [imo] he pushes the limit on its use. NFL needs to modify the parameters of the tactic.
In any other context on the football field, hands to the face would draw a 15-yard penalty.
But for some reason, a runner with the ball can literally strike a defensive player in the face to gain advantage without consequence. Makes no sense.
Should be a spot foul.
I have no problem with the use of the stiff arm, as long as it's not deployed on the face or head area of the opposing player.
This limitation addresses fairness of competition as well as consistency with rules on the books regarding hands to the face.