Has anyone tried William Parry's book/method?

Has anyone tried William Parry's book/method? Just discovered this subreddit. Awesome! Most web forums about stuttering are almost completely deserted. Finally a place with some activity. :) Anyway, the book I'm referring to is [Understanding and Controlling Stuttering](http://www.amazon.com/Understanding-Controlling-Stuttering-Comprehensive-Hypothesis/dp/1929773242/ref=sr_1_1?ie=UTF8&qid=1436660881&sr=8-1&keywords=understanding+and+controlling+stuttering&pebp=1436660882604&perid=1N198QWRAST9GGG7T16S). I bought his book a long time ago (2001 I think). It was the second edition IIRC. Anyway, I read the book and I've been using the self-therapy proposed therein with some pretty good results in general. I'm still a victim of the sort of yoyo syndrome every stutterer experiences in his life (good day, bad days, very good days, very bad days), but in general I would say the improvement is significant. I started in 2003 and did it for 30 minutes every morning like it is suggested in the book, until mid 2010. I started having serious health problems at around that time so working on my speech went down in my list of priorities and I stopped doing my vocal exercises. I started again last summer, so a year ago, and things have improved slightly in the last year. Most of the time I would say I'm happy with my speech but I still have very bad days once in a while (like today). So even though I'm improving, I still have a long way to go. I was just wondering if any of you had tried his method and what kind of results you got?