Well can anyone really control what thoughts come into their head? Generally I'd say no. But what we can control is how much energy we give the thought. We can choose to no latch onto certain thoughts, you can just let the thought go. You know that state you can be in when you zone out. In that state, you're literally thinking about nothing. That's the mental state you should he in after you catch yourself thinking about stuttering. Just turn your brain off and focus only on performing the task at hand. Another thing I want to mention is this whole thing about not wanting to stutter. I understand the feeling of not wanting other people to see you stutter because you find it embarrassing. I get that. But also recognize the power you're giving the stutter. It's like a school bully who's blackmailing you so you do what he wants. Maybe he's threatening to release sensitive information or something. But the minute you voluntarily tell everybody about the secret, that bully loses all the power he had over you. And you become stronger for it cause one less thing can hurt you. It's the same principle. Just stutter on purpose. Stutter like you're doing a comedy bit or like you're an actor in a hollywood movie. Just have fun with it.