We posted at almost the same time, so I think you didn't see my answer. [edit I see you did
] But since I see you've ridden a horse at a gallop I'll try to elaborate: while on that horse you were probably using your leg muscles to stay on right? Gripping the animal? In dressage you can't do that as every move of your body is a cue to the animal. The rider essentially balances on the animal, and uses their muscles to control his movements -- like lead changes (which forefoot is placed down first). It's very difficult and counter-intuitive when one is on a massive cantering animal. I've ridden a great deal and can't do dressage. I think Boss Radio's wife can though...