Play from a game not long ago:
On a planned play in B's red zone, QB takes a shotgun snap, fakes looking for a receiver very briefly, then runs straight ahead. Just before he gets to the neutral zone, he stops, jumps and pitches the ball forward to an eligible teammate. The QB returns to the ground, and is watching to see if the pass will be caught when a defensive player grabs him by the shoulder and yanks him down to the ground. Flag flies from the R for roughing the passer. Penalty is enforced. Team A scores a couple of plays later.
During the break before the K/O, the B coach calls the R over. Conversation goes something like this:
C (mildly heated): How is that roughing the passer?
R: How is it NOT roughing the passer?
C: But he ran with the ball, and then he just pitched the ball forward.
R: Did he throw a pass?
C: Well, yeah, but...
R: Then he's a passer. And when your guy yanked him to the ground, that's roughing the passer.
C: You mean when he's running like that we're expected to know he's going to throw a pass?
R: Yep. The rule applies to a player that passes the ball - no exception for what kind of pass, or what he was doing before he threw the pass.
C: We gotta do something about that. That's a bad rule.
R: Well, you need to call Rogers Redding.
C: I'm gonna do that - I know him quite well.
Sometimes we win.
