I feel you're right. I feel this vicious anxiety loop is something a lot of people dont want to talk about. I feel its the biggest factor in why we stutter. With me, I may have started due to low self asteem as a tiny kid and maybe being teased about saying something incorrectly once, making me anticipate something like that happening again, building an apprehension. Because as a kid, you generally dont want to put yourself in a situation where you will get teased. But, paradoxically, you build up huge apprehension towards ideas, and this apprehsion, I feel, is what makes us react with a panic response in our speech. Just my thoughts. :)