Sounds just like my Snickers, and, if Nibbles really is like that, you've got a very interesting, joyful and educational adventure ahead! Also, my experience shows that such horses need lots and lots of intellectual stimulation. They learn quickly and get bored easily if the same lessons are repeated frequently, so you have to be ready to learn to be very open to different approaches and things you can teach Nibbles. And one should never underestimate the intelligence, pride and, if I may say, spirituality of such horses... They are here to teach us more than we are to teach them.