I realise this is a bit old, but I've been reading some of his stuff on his website. I'm hoping to audit a clinic in April, so I'll let you know how it goes if I can make it! It's during the week, so I'd have to figure out how to get off work.
One of my instructors works with him and teaches with his practices. My horse has an odd lameness in his right shoulder that vets couldn't quite figure out. My instructor has helped me a great deal by working on strengthening muscles in specific areas at a time, with in-hand as well as riding. It's made a HUGE difference and the in-hand is a great tool, especially when bringing a horse back into work. I can't say enough good things about it. I would attend a clinic in a heartbeat if I were close enough.