I have a weird thing. Most times I can control my speech to like 95% fluency. But on the phone it drops to like 60%. One of the words I cannot say when in control of my speech at 95% fluency, is "I stutter/stammer/speech impediment". And on the phone, forget-about-it! I hate saying it and have found that when I do say it, I actually start to stutter a lot worse than if I dont. So I dont. Its like by saying it, I summon the stuttering demon. Sometimes, I dont even have to say it, if someone else says it to me eg "do you stutter?" ... the demon comes and sits on my chest and covers my mouth with his hand. it's terrible.