I can't say I've had experience with this specific diet, but I have tried to diet before by restricting to about 1000 calories. Each and every time, without fail, it set me up to binge (because of the same hunger you describe, and physiology, as well), and the weight always came back, or I never got to my goal to begin with. The more you deprive yourself, the more likely you are to run off the rails, in my experience anyway.
Also speaking from experience, the best success comes from making a lifestyle change, not a diet you go on and off. I would find it really hard to maintain a lifestyle of 800 calories, and depending on what food it entails, it might not be healthy. So I guess the question would be, is the fast loss at the beginning really worth it? If so, that's your choice, but there are (IMO) less frustrating ways to go about losing weight.
This time, I used the calculations of calories in, calories burned to lose 1.5 pounds a week...closer to 1 pound at the end. Doing it this way got me to my goal for the first time...ever. I am sold on exercise, healthy food, and a moderate calorie deficit.
"If you drop an egg, you don't say, 'Oh, shoot' and drop the other 11, do you?"
-Source unknown, but obviously brilliant
Reached goal 4/16/2010...but kind of afraid to look these days