I must admit that I was (and to some extend still am) skeptical. But reading the reviews, as you suggest, is indeed very interesting. The idea behind TMS is that one of the biggest and most important organs in your body (the brain) basically attacks other organs. That sounds a tad crazy on first thought. But no MD in the world would question that this is indeed often the cause of major illness when we look and another "organ" that's about as important as the brain: the immune system.
In completely unrelated chronic pain research, it is very well established that chronic pain is self-reinforcing. In patients with chronic pain, scans show that the pain center expands, and can take over parts of the visual cortex. One treatment for chronic pain is based on visualization of positive things, specifically to counteract this pain expansion / self reinforcement.
My wife has just gone through the medical standards in attempts to heal shoulder pain that originated from a few specific wing sessions. Her experience mirrors what many of the reviews state - lots of trial and error, and no success with PT etc. Fortunately, though, the MRI diagnosis clearly showed that there is no significant actual damage, just regular "grey hairs on the shoulder joint", to borrow that expression. It will be interesting if assuming TMS, and following whatever suggestions Dr. Sarno et al. give to cure it, will make a difference. In the reviews, some reported very dramatic improvements, while others loved the theory, but did not get any large improvements.
That said, I'd still be a cautious when it comes to actual neck injuries. Some of the race foilers seem to think they are a good idea. I usually wing at rather low speeds (below 20 knots) and never felt the need for a neck brace myself; but I have had much harder crashes when windfoiling and windsurfing where I thought that a neck brace would have been a darn good idea.