I have had a couple of opportunities to use aspects of physical aikido as well joint locks and unbalancing work rather well on uncooperative horses if you know how their bodies work.
Any chance of geting a little more detail on this? I find myself working with the more difficult horses more often than not (due to prefereing them, actualy. I find it more rewarding.) and any hint of things that can help me improve there would be apreciated.