Keeping in mind that I am not qualified to judge the medical efficacy of the diet-- the premise is to give your gut a chance to reboot and heal by taking away anything that is damaging, and providing nutrients to rebuild.
It starts as an elimination diet (the first few days you are only allowed bone broth, yogurt, and the juice of fermented vegetables). You'll be making all these things yourself, from organic ingredients if at all possible (is this necessary? Who knows).
There are 6 stages total, they gradually introduce more normal foods. You go from stocks, to vegertable soups, to boiled meats...
For me the difficulty was, going about my normnal day, and devoting several hours a day to cooking with a toddler to look after.
But I would suggest trying it if you're of a mind. I felt better almost immediately. My complexion changed, my mind changed. I felt like I was not at war with the world for the first time.
Infact, just talking about it Im considering starting it again. :)
The author seems to be anti-vaccine. Or at least, she suggests postponing child vaccination until age 4 or 5.
It's also worrisome that the FAQ has a section on "PARASITES & WORMS":
"Generally speaking, worms and other parasites are an inevitable part of life, everybody has them. In the majority of people they cause no symptoms and, unless they cause problems, there is no need to attack them. Worms may fulfill some useful functions in the body by controlling other microbes and stimulating immunity. For example, it has been discovered that some worms have a balancing effect on the immune system and may prevent autoimmunity."