I hear this all the time, no matter how confident I am it's a guarantee I'll run into some blocks. But it's all about stuttering comfortably, of course I'm going to stutter but using some of the techniques I've learned in speech therapy, it makes it slightly easier. Although those techniques don't always work, when they do it feels a lot smoother and is much less of a struggle. Sometimes no matter how confident I feel and how hard I try to use my techniques nothing comes out, but that's living with a stutter and you can't do much about it.