Yeah it does look impressive doesnt it. Really must need a long high wall and perfect timing. I experimented on the weekend getting along the face and lifting my knees which takes you to the higher part of the wave, then I kind of tried opening my shoulders and extending my front leg (dropping the back leg) to take the board from the top to the bottom again. Have not quote got the wieght distribution right, its so easy to bog a rail, or not catch the rail, and eat it.
Watching the guys who do it well, they keep their wieght central to the board which gives them the balance and abiltiy to keep the board under you at all times and not extending past where you are on the face.
Man that sounded technical! Hope it makes sense, cos Im not even sure after reading it