I have the same sort of problem. all my worse stutters come whenever I'm trying to make a point or reading text out loud. the best fixes were to avoid thinking solely about those things. do you stutter when you sing? if not, focus on the pitch of your voice. not a singer? try thinking about the enunciation and pronunciation of the words. i find i stutter alot less when im solely focused on the delivery of my words rather than their meaning or implications. so i end up monologueing in private to practice this. thanks to to that i went from bombing my speech class one semester to aceing it the next. you can do it OP!