I remember once being kinda skeptical about the book Ratio a while back, but I saw a copy around here and skimmed it and found it very pleasing. I think my skepticism was based in thinking "well, of course it's the ratios that matter, because everyone knows that you can double a recipe to make more". The book's point seems more... pointed, though. It specifies which ratios it thinks are most important, most essential to various food-genera. And the pedagogical style is refreshingly honest about the fact that the ratios given are just first-order approximations to what is anyhow an ultimately subjective system of classifying foods into types and suchlike. I find I really like the structure of "okay, here is the basic idea, stripped down as much as I possibly can to leave it still recognizable as the thing you want to make, with no bullshit... and then here are eighteen variations you might want to try after that." I feel like I'd like to see this applied aggressively to teaching other things to see how well it works. It might well not work, because cookery is cookery and, say, programming is not quite the same. But who knows. Could be some useful ideas there.