Just remember that what works best for one person's body shape may not work best for someone else. My instructors advocated different positions, but were open minded enough to work with each shooter to find the best, Most natural position. Then they allowed the shooting to decide which was best.
The creedmoor long range position, (Shooting resting the barrel on your foot and laying backwards to the target with Iron sites @ 2000 yards, is/was the worst/most uncomfortable position I ever shot
and the shooter just has to find the best position for him in order to have the chance of hitting anything at 2000 yards. (No optics or rest except the body.
I still think that there is no one position for everybody, so try different positions and let the shooting decide. There are many other things that effect the accuracy of the position that can also determine the best position for the shooter including the rifle type, shape and weight. I found that I needed to change my position from shooting an M1 or M14 to a bolt gun. so I find making adjustments for the rifle and the match shooting or hunting required being flexible makes a difference in my shooting.
Each to his own, What works for me may not work for someone else. But I don't recommend practicing something that Is not best for you. You can train to do something wrong and your body will adapt, but if you learn something wrong for you the lack of performance will follow you and be hard to correct.
We are all individuals and every now and then we have to adapt to ourselves.
J E CUSTOM