Another thing to add to figuring out what maneuver gets the 0... the pilot was coming out of a square loop (from the top in this case) where does that maneuver begin/end.. at the first radius, or in the center or the line preceding the first radius? (just curious as it has never been an issue in anyone I have judged that it would have changed anything, but I could see in this case how it could be depending on where the roll occurred as to weather the square was complete)