I think you need to be clear that its not ethanol that is making people's stutters better, it is the fact that they are intoxicated and less nervous when speaking to other people. You will see the same results with mild sedatives and anti-anxiety medication, as well as meditation. There is a deep link between smoothness of speech during social interactions and speech performance, where often poor performance has a negative cascading effect on speech, which of course provides negative feedback for speech performance. The alcohol/other substances simply provide a block of this negative feedback - where the speaker is much more relaxed and doesn't get tripped up as much as they normally would when they stuttered. I would be interested in what conclusions you draw, please keep us posted.