the position they are showing is incorrect. thats the old way. if your body is off to one side like that then your shoulder is no longer level and the recoil tries to escape out your shoulder instead of going through your whole body.and then every time the rifle recoils it will want to jump to the left or to the right depending on which direction the shooter is off to. kind of like what they say in the magpul videos that you need to get your shoulders level and agressive on the rifle. same idea in a sense. this becomes an even bigger problem once you start shooting off a bipod and are no longer supporting the rifles forend with your off hand. to shoot optimally off a bipod once the rifle has recoiled it should rest back right where you were origonally aiming and you should be able to watch the bullet impact the target through your optic.
so the correct position is with your spine parrallel to the rifle (more or less) shoulders level, and feet layed out flat (if you can some people cant do it) and with legs spread out a decent amount.
This video isnt specifically talking about shooting position but you can kinda see how hes doing it.
