[PSU213]

Originally posted by butkus
As far as the question of whether the pylons are inbounds, the Rulebook states:
The four intersections of goal lines must be marked at inside corners of the end zone and the goal line by pylons mounted on flexible shafts. Pylons must be placed at inside edges of white lines and should not touch the surface of the actual playing field itself.

There you have it. The plane is only vertical because the ball has to be on, above, or behind the goal line, and MUST be possessed by an offensive player who is INBOUNDS. The ball can, however, touch the pylon because the pylons are inbounds.

Mystery solved!

Even in the NFL, the pylons are out of bounds. It is a TD when the player touches the ball to the pylon because the pylon lies beyond the plane of the GL--the ball would have to cross the plane in order to touch the pylon. Unfortunately based on the rules you stated it does not definitively answer whether the player must be touching inbounds to take advantage of the GL extended. The goal line extended is probably dealt with in the definitions section of the rules.