In my experience, when I approached a role, I completely immersed myself in that character and I read all my lines through the eyes of that character. I have a moderate stutter (downgraded from Severe). When I read those lines I was not myself, I was that character and that character did not stutter. Just my 2 cents. (Background: I'm 49 years old with 20 years of speech therapy. I've acted in many plays, performed prose and poetry readings. )