I am basically just a hobbyist when it comes to throwing/pitching mechanics and training/conditioning. But, being more than a little OCD, I have studied the "gurus" extensively. For my money, Graeme Lehman (@GraemeLehman) is one of the best follows on the internet. He is clearly a very bright guy. But, he's also a very good communicator, without the hubris that you get from a lot of these guys.