I'm a bit disappointed. Not as much Alton as I'd hoped for. Maybe there will be some deleted footage on the website. I would've liked to see more of a Mythbusters/Good Eats hybrid where Alton presented some actual recipes, or have him do more of the hosting. The popcorn segment came closest to what I wanted to see, with Adam, Jamie, and Alton all tag-teaming as presenters and geeking out together on the technicalities of the experiment -- although that wasn't so much testing a myth as testing a product. Plus we got a bit of an Alton Brown food-science lecture with the popcorn, though I wish he'd worked with Adam and Jamie to concoct one of his cheesy large-scale models for demonstrating the physics or chemistry of cooking. Or maybe buit some kind of large popcorn-kernel analog which they would heat until it blew up.
Oh, and the slow-motion shot of the popcorn falling was very pretty. I wouldn't want to eat it after that, though.
The car-cooking myth was kind of fun, though, even if Alton seemed a bit more marginalized there. It was really more about logistics and preparation, I guess. It's impressive how successful they actually were at cooking the whole meal. But while this myth would count as plausible, I doubt your average person could pull it off without the right kind of old car, a lot of thermocouples and appropriate software, and the aid of a skilled and creative chef.
The other guys' myths were kind of basic. Nothing very elaborate this week, just straightforward (if messy) tests of rather simple questions. The main thing I wonder about the tryptophan myth is whether it was appropriate to test the guys' reaction time immediately after eating. I think it would take the tryptophan a while to kick in fully. Still, I'm sure it's true that just eating a large meal is a greater component in the sensation of relaxation or sleepiness. For one thing, your energy's going into digestion, so there's less available for the rest of the body and mind.
On the "tastes like chicken" myth, I wonder if it was appropriate to test the foods side by side with actual chicken. I think it might be more likely for an exotic meat to remind you of chicken if you hadn't just tasted the real thing. Then you'd be more aware of the similarity than the difference. So maybe they should've started out with a taste test of the exotic meats without any chicken to compare them to, and then done a test combining both chicken and exotic meats, and compared the results.