REPLY: Consider it this way...If a ball in a runner's possession crosses the plane of the goal line itself (i.e. inside the pylon), it's going to be a TD regardless of where the runner's body is--as long as he's not
touching OOB. However, it's also a TD if the runner crosses the goal line plane and touches the endzone inbounds regardless of whether the ball is inside or outside the pylon. The goal line extended concept is there to cover the play where a runner goes from the field of play into the EZ just inside the pylon where he's carrying the ball in his outside hand. In such a case, the ball may be outside the pylon and not cross the goal line itself. When I first typed this, I thought my explanation was pretty clear...now I'm not so sure.
I know what I'm trying to say, but I'm not certain that anyone else will !!