Appetite driven obesity or hunger driven obesity? why not both, the mild cases have one or the other, we extremes have both.
When hunger strikes we eat, but it is easier to not eat with hunger as the driver than with cravings as the driver. When cravings strike we have little choice but eat or refocus, resist, go away. Either way, we are eating too much.
Danish volunteers who are paid to overeat spike insulin from 35pmol/l to 74pmol/l in just three days. Mice with zero leptin overeat massively, but do not show the same insulin spike. The insulin spike signifies insulin resistance, that characteristic antioxidant defence response to an excess of calories in the metabolic milieu. This does not happen with the early overeating phase of ob/ob mice. They are in metabolic caloric deficit, which they make up by eating enough to remain vaguely functional.
Absolute leptin deficiency appears to be a very harsh driver of fat storage. Losing this many calories makes you hungry. I guess some bit of the brain is involved in converting this state of actual calorie deficit in to a feeling of hunger, but that's not what interests me nearly as much as what is happening at the adipocyte level of calorie storage.
So what does all this mean? Do not eat no mater what, and when your ass falls off, oh well. Set carbs as low as practical, proteins as low as practical, fats as low as practical, and we should lose weight. Right? but some of us do not, so we need to cut further. Into hunger and craving territory. But hunger is relieved with just a little food. It is those cravings that cause the problem.