I don't know much about training horses although I have been around then a lot. I used to be a hot walker for race horses ( that Job didn't last long after I seen what they do) there was one horse that EVERYONE was told to avoid cause he was a biter and not nice easy nip,, the I'll do as much damage to you kind of bit. After having to walk the horses around this one all the time and him lunging toward you to get you, I balled up my fist and as soon as he tried I popped him as hard and fast as I could in the mouth. He never gave me ANY guff after that. The owner actually asked me what I did, I was afraid to tell him, but he wanted to know cause I was the only one he wouldn't try and bite. So I told him. Got a raise and asked to do more work around him, 2 days later I quit.. that's another story.....