But of course, the QB can intentionally put a little backwards motion into the pitch to cancel this out so that it truly does not go forward.
I feel like a nerd typing this out. I think it was Mavric who mentioned he was looking it up in the rule book to see whether this was accounted for - which if it is, then ignore everything I'm saying.
I'm just pretty sure though that according to the rule book, there is no distinction between a "pitch," a "a lateral," and a "forward pass" as it pertains to whether or not the ball goes forward for whatever reason. If the ball goes forward and the person committing this action is past the line of scrimmage, it's an illegal forward pass.