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In the old days, defensive players could stuff the quarterback. The old days are dead in the NFL. They will never return.
Rule 12, Section 2, Article 11, subparagraph b: A rushing defender is prohibited from committing such intimidating and punishing acts as “stuffing” a passer into the ground or unnecessarily wrestling or driving him down after the passer has thrown the ball, even if the rusher makes his initial contact with the passer within the one-step limitation…
Tackling/sacking the quarterback is a mental exercise in 2022. It's not 1972 anymore. The NFL does not want its quarterbacks pounded through the ground. The rule is an irritation if the player is not intentionally trying to injure the quarterback but not THINKING beforehand will result in a braindead penalty and should fall primarily on the player's shoulders only in my opinion.
Rule 12, Section 2, Article 11, subparagragh c: A defensive player must not use his helmet against a passer who is in a defenseless posture… (2) lowering the head and making forcible contact with any part of the helmet against any part of the passer’s body. This rule does not prohibit incidental contact by the mask or non-crown parts of the helmet in the course of a conventional tackle on a passer.
On the other hand, I believe coaches and player bear equal responsibility for erasing this tendency from inside the player's head. All the player needs to do is keep his head up. You must see who you are going to hit anyway. Eyes up. Less chance of a stupid penalty. Eyes down. Almost always a braindead penalty because the refs do not give a flip what part of the helmet hits ANY part of the quarterback's body.