This is true for me as well. I think it's to do with a couple things. The flow of consciousness that pours out when your angry, there's little time for thought about what you're going to say, *it just gets said*. Also the fact that when you're in that state there's almost no space left for any anxiety around the stutter, you often feel in control of the situation and yourself - you're confident. It's actually problematic sometimes because it makes anger appealing, even if only for the brief breath of fresh air that is fluency.