Dramatic low-carb dieting just doesn't work for everyone. I have a friend I've known since I was three or four who switched to a low-gluten, vegan diet and she's never been in better shape in her life. I wasted away (in terms of energy and muscle, not fat) on a vegan diet. Grain- and starch-free is the only thing that works for me.

I agree with AnniMin that he sounds discouraged. He made a few logical fallacies, which I found surprising since he's usually on his toes. Maybe he's taken on too much. I don't think Taubes set out to become the figurehead for an entire movement against the modern food system.