PC, very interesting results. Thanks for sharing them. My experience is similar in that it feels like I'm eating to bursting, but I'm actually getting a lot fewer calories than before PB while my activity level and muscle mass has increased.
I put it down to an increase in metabolic efficiency. When the body gets an optimal mix of micronutrients, proteins and fats, it can really stretch out the calorie budget like never before. The longer we stick to the PB, the more efficient our metabolism seems to become. Having warm hands when they're usually cold, to me, is a sign that you now have surplus dietary fat that's going straight to thermal energy (like Molecular Grokologist explained).
In the end, the only metric I pay attention to is my energy level. How many pushups can I knock out? What kind of pull-ups can I do on the tree? If I'm pushing my records, then I must be getting the right nutrition, even if it seems like it mathematically couldn't be enough.