The more you want to speak, the higher the dopamine level gets. You're a very desperate stutterer, so you stutter severely. It's the same (or more precisely: the opposite) as in premature ejaculation (pagoclone had been developed for that problem) and in Turette syndrome. You can't resist to not stutter. Or much more precisely: you can't resist to speak well. You want it so bad, hence you stutter. Stuttering is a delayed ejaculation.
It's a primal urge in you.
I wonder, why.