I have no specific experience with stuttering but I have micro-dosed and occasionally macro-dosed psilocybin for years now and it has completely eliminated a number of process addictions and a compulsive self harm behavior that I had developed as a result of growing up in an alcoholic abusive home. I think the approach that is often espoused of taking tripping size doses to cure long standing issues is not necessarily the right approach. I think that long term micro-dosing is a more effective strategy because it just gently and slowly makes positive changes in the mind, tripping is trying to rush things imo.. The way it seems to me is that mental health issues take time to develop and like when trying to straighten a bent tree branch a slow and steady pressure will straighten the branch far more reliably then a large and quickly applied force will, the large quick force risks breaking the branch. Micro-dosing has cured issues that I thought would never go away for me, as well as the addictions and compulsions it has ended all of my chronic anxiety and depression. It's very safe, especially when micro-dosed, and if I or someone I knew had an issue with Tourette's or stuttering I would definitely recommend that they try micro-dosed psilocybin. It would probably be worth their trying macro-dosing as well after they have micro-dosed for a while. Tripping without ever having micro-dosed is not something I would recommend, as any preexisting issues with anxiety will potentially lead to a bad trip. micro-dosing first minimizes the risk of that happening. If you can get hold of some mushrooms there really is no downside to trying them to see if they work for you.