I have no tics, which is what made me move on from Tourettes when I was researching it. I can always control it, but I don't know where it comes from.
I have gotten myself in a few minor problems when I would say something inappropriate, but I've never said anything outright rude that I was thinking.
Sometimes I think of things just for the sake of then thinking about how someone would react. Once I was being interviewed by a male president of a company and his female daughter employee. I kept wanting to say "stupid blah blah, you are a dumb stupid prostitute" just to see how she would react. Would she kick me out immediately, what would she say....stuff like that.
My self defense mechanism is to just be quiet. I'm pretty quiet now, but inside I am thinking awful things.