The series is in a weird place in between Mind of a Chef (which, in most of its seasons, is a significantly better show) and a more conventional FoodTV cooking show. I think they're trying to do too much in each episode, and also that the travel-show part of each episode works better than the cooking demos do.
The book is better than the show. I have friends that swear by it. I like it fine! It sort of joins a pantheon of "if you're only going to own one cooking book make it this one" books, which would include Bittman's "How To Cook Anything", Ruhlman's "Twenty", the Cooks Illustrated Cookbook, and, I don't know, maybe "Joy of Cooking"?
Of those books, I think Ruhlman's "Twenty" is by far the best. It's similar to "Salt, Fat" in the sense that it breaks cooking down by technique and concept, instead of courses or dishes. But I think it has a more coherent structure, covers more ground, and, while wasting less time on narrative, still manages to establish a conversational tone.