I do this... I often have too many ideas im trying to get out at one time, and my mouth and brain are functioning at different speeds. I find interestingly enough that is why my handwriting is poor as well. I want to get a slew of thoughts out, but my hand or mouth cant keep up.
I dont consider myself a fast thinker, I can have a way of condensing ideas in my head and once they get out of my head they are alot bigger, kind of like a bag of vacuum sealed full of blankets. Once you break the seal and introduce the blankets back into the world they immediately expand, I think my ideas are more condensed in my brain, and when i try to get them out they take up more space and so my brain and mouth are firing at different speeds and i stop or sputter when they come out of my mouth or even on paper. Its kinda like an engine that has its piston timing off.
The blankets expand , because the vacuum bags contain a different atmospheric pressure. I guess you could say that my thoughts have a different atmospheric pressure once they are released.
That probably sounds like gibberish, but it makes sense to me. lol My brain and mouth no work good when speak.