I think it's pretty clear that one principle holds true in training any living thing: ask once, then correct if obedience does not follow. We used the technique to the best of our ability in training DaVinci, the dog, and we've had good fruits in all areas where we were diligent.
I'm finding my limits with Flame, the horse, though. Though a beautiful animal, he is too smart for his own good; or, at least, for my good. He spends far too much time and energy figuring out ways to avoid work and difficult situations instead of just cooperating as most horses do.
Dressage and hunter/jumper disciplines are dependent on using the body to communicate with the horse, rarely the voice. So I have to rely on my calves, thighs, seat, upper body, and hands to ask/tell him what to do. Trying to get all those parts doing the right thing at the right time without sending confusing or contradictory signals is quite a challenge, especially then flying along at rather swift speeds around and over obstacles. So, if Flame doesn't do the right thing, is it him or me? Is he being disobedient or did I not ask clearly? Do I correct his mistake or apologize for mine? In the end, we always finish on a good note (even if it's only minor) and then he gets his sugars, but it's all the exercises leading up to the happy ending that stretch us both.
Through all of this, though, I am learning to see how an obedient spirit and a willing heart, even one that makes many mistakes, would be priceless. That is the attitude that can be shaped into anything, molded with unlimited potential.
That must be the mount Shakespeare's King Richard III was desperate for when he exclaimed "A horse, a horse! My kingdom for a horse!"