It's technique, though not fluncy shaping (the technique is coastal breathing). I know friends who have done it and done really well, I know other people who have done it and while they like it, they continue to have the same struggles that graduates of fluency shaping programs have. The breathing technique is one part of McGuire, the other part is the support (peer and group support) and they do focus on being comfortable with yourself and living your life. In my opinion, I think there is some cognitive dissonance between accepting your stutter and trying to control stuttering. But then again I've never done McGuire myself so I may not be completely accurate. Are you in Europe?