That's how "techniques" usually work. They're not magic. They work in therapy, they work in controlled situations. Thru may transfer to the real world for a period of time but most of the time they fail when you need them most. It's not you, it's the nature of techniques for the most part and for the majority of people. Also most people don't want to use unnatural techniques even if they think it will help control stuttering. What's the point of fluency if you have to do it without naturalness and joy?