I really know how that feels. I think I tend to do the same thing but usually don't realize it. Typically with a lot of "uh"s. What really sucks is when people don't know that I have a stutter and they just assume that I say "uh" and "ummm" a lot because I'm forgetful or slow. When in reality, I know what I want to say, but I just can't. Like what really pushes my buttons is when people ask me my name or my age, and I tend to respond with "uhhh, Kevin", and they ALWAYS respond with "well, you had to think about that eh?" That fucking kills me on the inside.