Well, I don't know about you, but when I eat, say, a ton of dry chicken breast, I have no appetite. My first foray into Atkins was high protein, and lots of weight loss; later I tried real ketosis (higher fat), and found it hard to sustain. My experiments with IF and high protein leave me satiated with half of maintenance! So for me, at least, there's some magic with protein and satiety. According to Taubes, the magic is low carb and the evils of insulin, but high fat, low protein should work better, and it doesn't, for me, at least.
That's all n=1 stuff, but there are some studies that support this (with diet, at least, n=1 is the only thing that counts but it's nice to know that it's not purely mental). Now, satiety is another way of saying better leptin sensitivity or higher leptin (or there's some other magic unknown hormone).
Here's what I know: strategies to manage leptin work for me; strategies to manage insulin don't. I don't really know what is going on physiologically: is it leptin, insulin + leptin, something else?
The best strategy for me (n=1) is IF + high protein/low carb with occasional post workout high carb refeeds. Leangains, in other words.
Lyle had a whole series on leptin on his site; it's a good read.