Yes, precisely. But I'm talking about the limits. If you ingest fewer calories than you burn you will lose weight, period. That's the argument that people have been making about weight loss for ages. But the difficulty there is that in reality the range of "thermodynamic calories" that a person can ingest relative to the exercise they do while maintaining a healthy weight can vary across a huge margin.
I recall reading about an experiment where obese mice were injected with insulin regularly after being denied food. The mice starved to death despite still having fat stores.
Of course, mice are not humans, but this implies that diets that stimulate a lot of insulin production (or normal amounts in insulin-resistant populations) would cause a person to not lose fat.
