I didn't sense any of the "negative energy" mentioned by the previous reviewer, but there is one crucial thing you need to know about Austin Flint: He talks. A LOT. This wouldn't be so bad if he was talking about the piece being workshopped and giving helpful advice, but instead he constantly goes off on long tangents about former students. At first these anecdotes were amusing, but the act quickly got old when he just kept going ON AND ON and he was essentially saying nothing applicable to the work in front of us. There is something seriously wrong with a class when people get only 20 minutes to workshop a piece they've put a lot of effort into completing because the instructor is too busy telling stories about former students. Also, time management seems to be a problem: If you're the first person up to be workshopped on a class day, you might get an hour. If you're last, have fun with your twenty minutes.
I mean, he's a genuinely nice guy, very warm and sweet. And he truly seems interested in your writing - his written comments were helpful. Obviously he has a lot of experience in theater. But this is not the best way a workshop can be run. If he wouldn't talk so much about his former students then we would get a lot more done.