Quote:To humor you...


2002:

"It is illegal to hit a quarterback helmet-to-helmet any time after a change of possession."


2006:

"Low hits on the quarterback are prohibited when a rushing defender has an opportunity to avoid such contact."


2009:

"It is an illegal hit on a defenseless receiver if the initial force of the contact by the defender's helmet, forearm, or shoulder is to the head or neck area of the receiver. Penalty: 15 yards."


"Clarified rule regarding low hits on passers:

A defender cannot initiate a roll or lunge and forcibly hit the passer in the knee area or below, even if he is being contacted by another player."


2010:

"A player who has just completed a catch is protected from blows to the head or neck by an opponent who launches."


"All 'defenseless players' are protected from blows to the head delivered by an opponent's helmet, forearm, or shoulder."



2011:

"A receiver who has completed a catch is a "defenseless player" until he has had time to protect himself or has clearly become a runner."




All of those rules, comebined with the obvious crackdown on illegal contact penalites since 2004, has led to inflated passing stats. This is obvious to anybody with an ounce of common sense.