this actually sounds like a really interesting case, especially since your own SLP said the traditional techniques don't apply to your pattern. The fact that you're fluent under high pressure but block in relaxed settings with people you're comfortable around is definitely counter to what most people experience with stuttering. I'd really suggest checking out Better Speech since they have licensed therapists who work with all kinds of stuttering patterns, including more unusual presentations like yours. The virtual format also means you could potentially try a few different specialists until you find someone who's experienced with impulse-triggered blocks rather than anxiety-based ones. One thing that stood out to me is the contamination effect you mentioned, where one block seems to activate a mode for more blocks. That does sound like it could be a learned motor pattern rather than something purely neurological. Some approaches like the McGuire Programme or even ACT (acceptance and commitment therapy) focus more on breaking those automatic responses rather than just managing fluency techniques. Since you're in Germany, you might also want to look into whether there are any clinics that specialize in neuromotor retraining for speech. The reset after stopping for several minutes is fascinating too. Makes me wonder if there's something about sustained conversation flow that triggers the motor pattern, almost like your system gets stuck in a loop until you consciously break it. Anyway, hope you find someone who gets your specific pattern becuase it does sound solvable given how clearly you can identify the triggers.