As has been said word substitution is an avoidance technique that should generally be, well...avoided. But I don't think you necessarily have to give up on speech therapy assuming your therapists is open minded and you both do some homework. Personally, I attend speech sessions run by speech-language pathology grad students looking to get clinician practice. Although the students are very new to speech therapy, and the program director was very unfamiliar with the therapy that I identify with (avoidance reduction therapy), it has been a overwhelmingly positive experience for me. The students/director were very happy to learn what they could, helped me set/reset short/long term goals, and I met with them regularly to practice techniques and report on any past accomplishments/"failures" I've had since I last met them. What I'm trying to say is if you are stuck with your therapist and therapy is something you are interested in pursuing, maybe you can do some research into therapy styles that you think you could benefit from, and discuss with your therapist about them/set out some goals that they can help you reach. Obviously, It does seem somewhat foolish that you are essentially doing a large parts of your therapists job for them, but if you are stuck with them they can be a useful tool to help you reach your goals. This subreddit has a couple of resources that could help, but I definitely recommend the [Self Therapy pdf](https://www.stutteringhelp.org/portals/english/book_0012_tenth_ed.pdf) to start off. Hope this helps!!