Well, sure, I kept my weight off eating low fat and exercising, just like I was supposed to. It did work.
As soon as I got sick, and couldn't exercise at that level, it came back. Unless I ate less than I wanted. Which I couldn't keep up, being sick. Kept creeping up...got better, exercised more, but now I'm older...hard to keep up that level of exercise.
Low carb works, at my greater age, with a pretty good activity level but not as much as I used to.
I think the emphasis on exercise is so great because it's the only way low fat DOES work. Ya gotta burn off those carbs. If you can't keep up with the carb burning activities...it doesn't work.