This person makes a lot of sense and their experience shouldn't be quickly dismissed.
I've seen people lose 60 pounds just from eating the right foods. Surely, if you ate whole, unprocessed foods, you could at least keep the weight off.
Fasting is great for weight loss but it's also important to learn healthy eating habits so you don't go back to that place again. I guess it depends on what people want, how they want to live, and how badly they want it.