I have the book. It has helped me a lot. Not saying everything in there I agree with or I think is perfect. However, I think the main idea that the book provides and that has led to success in my life is to try out different ways of saying things. Since stuttering is a feedback loop to an extent, breaking that loop to start having different experiences and everything associated with those is game changing. Obviously, stuttering for me has not completely gone away, but it has improved greatly. And in those moments where you do stutter or feel like you will, you will start caring less if you do or don’t, and if you do, you will be more confident is handling it gracefully. Speech isn’t about raw perfection, it’s just communication.