I watched this episode with my kids last night and I just want to say that I thought Animal Planet actually did a very nice job making it clear that a miniature horse should never be ridden by an adult. They did have an experienced falabella breeder doing the commentary for this story and she stated several times that the adult was at fault NOT the mini!!!
She clearly stated that the horse was scared and attacked out of fear-rightfully so-and mentioned that no adult should ever ride a small pony, she further went on to say minis under 30" should never be ridden by a person of any size.
I too worried at the start of the episode when I saw the video of the attack that the show would point out the fault of the horse and not the stupidity of the 5'9 200lb male riding him. BUT I was pleased to watch as the story developed and they did defend the actions of the animal. Even the Argentinian fellow who made the very poor judgement came forward and admitted that what he did was foolish. In the end I was glad to see the horse still resides on the ranch and has his own space where no one will ever ride him.
All in all in the end I think it was a good thing for people to see-if you intentionally do something that is harmful and just stupid to an animal you might just get what you have comming