Question about "Dell Ferro" therapy method.

Question about "Dell Ferro" therapy method. Has anybody ever tried the "Del Ferro" method. Recently I found out that this therapy (Offered in Amsterdam) can cure stuttering. From what i found out is that this guy named Del Ferro by accident helped someone lost their stuttering and then he began a treatment named after his last name Del Ferro. Now im asking if anyone has ever tried this therapy and can you share your experience with Del Ferro.