It does, and I think the opposite may be true as well. I was a test subject in a speech therapy study a while ago. The basis of it was essentially talking a TON in different situations and recording and analyzing the recordings to see if the varried and aggregate practice helped. My speech improved quite a bit because I was talking so much. Most of the hours were speaking smoothly until I couldn't, then starting over when I blocked--kinda like interval training for stuttering. But as soon as I stopped the study and stopped practicing thungs went back to "normal" pretty quick.