My parents would say "don't stutter" every time I would stutter. Like, thanks. You cured me. About thinking before you speak, I definitely don't think it helped me at all. When giving speeches in school, even though I would have every word prepared and written out, the anxiety of being in front of the class combined with the self consciousness of my parents constantly pointing out my stutter but doing nothing to help me resulted in all of my worst blocks being in front of the class.