It works for some people and it doesn't work for others. It didn't work for me. Have a long conversation with your speech therapist about their methods, proof of effectiveness of those methods, and how to mange your expectations. It's also a good idea to do your own research about different methods and then confront your speech therapist with detailed questions about the merits of different methods and why they are choosing the method for you to try. But remember, the best way to deal with stuttering is to accept it and learn how to cope as a self-confident person with a stutter, using a few methods to reduce your stutter, than to simply hope therapy will make the stutter go away forever.