When calories are strictly controlled there is NO difference in weight loss between people eating HFLC vs LFHC.
Still, I think that there are two big benefits to primal compared to a conventional calorie restricted diet:
1. You are eating tasty food you enjoy rather than tasteless low fat foods
2. You don't have feedmefeedmefeedme low blood sugar moments every three hours because you are fat adapted rather than running on glucose