Its the knees bent thing. Your stances are just variations of that basic depth, and why not fight at that level?Horse stance is there to teach you how to drop your body weight and keep your balance (back straight, bent legs, rather than the other way around). You will be in it fleetingly, it is a postion you pass through. It's not a position you get into and then fight, so I don't understand why you need to be able to stay in it for hours?