Putting them out to grass does so much, my hard to keep horse is now healthy and well looking like this since I moved him to field board. He is also an OTTB, but I have no idea how he won any money, he is lazy and needs so much leg to keep him moving in canter. There are plenty of TBs who are crazy, but there are plenty of sane ones too, I have owned my fair share of both. The individual horses personality is stronger than the stereotype.
I too have owned both naughty and nice TB's and I swore to never get one after my latest crazed one but I ended up and I to found a diamond in the rough! He was broken and lifeless. Now he is vibrant energetic much like the sounds of your boy. Its nice to know that someone else out there has become to reconigse how truley special this breed is and they are cabable of soo much more!! So thank you for giving this boy hope and helping him on his final straw! I beleive he would reconigse and appricate that you stoped and noticed!!