I know someone who bought one of his books expecting to learn some training techniques from it... But instead it turned out to be a story on his life.
But then again, a fraud wouldn't be allowed to work with the Queen's horses... hmm
Too much controversy surrounding him. His family said his book about his life was a pack of lies, people he mentioned in the book said stories he related are made up. However that has nothing to do with his training skills which I don't really know too much about EXCEPT....there was a lady that lived here and she was fairly lousy rider, horse handler, nice person though. She went to his training school or whatever he has, she paid tens of thousands of dollars to be certified as one of his trainers. I saw her work with a horse after she was certified, if I was her I would've asked for my money back, she hadn't improved much, in fact she couldn't get her horses in her trailer and her & her husband walked them the 5 miles home.
I knew a guy that had dated one of Monty Roberts adopted daughters for quite some time. His owns kids didn't even like him from the sound of it and the guy I knew said he wouldn't let him any where near of his horses. Also worked for a trainer that used to show against him and said the same thing.