Part of it Jeff, its all as ive said beforeOral stability, posture of the Head. If your chin is down more than 15% it alters the biomechanics and pscychodinamics of utilising gravity. Plus it stops the diaphram from working as it should by 50%, starving the eyes and senses from working as they should through lack of oxygen. Plus it puts the Head 6inch nearer that which is trying to hit you and usually on your front foot with knowhere to go, confused