I really don't think it's something you have to "tell" (or not tell) people you work with per se. It's clearly obvious to my co-workers that i stutter. Does "officially" revealing such a thing make it less awkward when you do stutter, and they don't have to tiptoe around how to react/behave/respond? More than likely, yes. \[Having said all above\^, i'm not against giving it a try and seeing if a different dynamic ensues.\]