It Is Important To Do This When Jumping! 

I wish you talk about exceptions more. "Keep knee behind foot pegs" is confusing description (for me, at least). Behind foot pegs in respect to the ground or bike? If you draw a line from knee to pegs, it can be perpendicular to the horizon, or to the local surface. Ground "rotates" on jump face. In other words, you can 'glue' legs to the bike in attack position and I guarantee that you will crush such way on steep jumps. Because, you actually move knees forward on bike. If you look recent footage of AJ, knees are on radiator shrouds almost on all steep takeoffs, which contradicts the advice without clarifications.