I had a horribly seized neck a while ago where I couldn't look over my left shoulder. This had come on after visiting a physio for a very stiff upper back (a legacy of military service and lots of programming). I bought the book after reading about it in the 4 hour body and did 1 set of the exercises. My neck had more range of motion after 25 minutes than it had for months and several hundred pounds worth of physio appointments.
This and other information on self treating trigger points (http://saveyourself.ca/tutorials/trigger-points.php) has got my back in better shape than before I joined the marines!