Had the opportunity to attend the Gatwick users forum couple months ago, and most informative it was.
One point that came over and bashed me over the head was the point on runway incursions. I always thought that this was entering or almost entering an active runway uninvited. (The actual paved bit)
News to me was that even with the nose of a/c protruding over the holding point line (even with nose wheel behind it) amounts to a runway incursion. Since then I must confess I tend to back off a bit now.