Never heard of it but just Googled it. Sounds highly impractical.
Limits you to one food category per day for a week? Then you resume "normal" eating for three weeks and then repeat, plus throw in an hour of walking every day. Other than the hour of walking quite frankly it is a joke. While there might be potential to lose during that week, you could easily gain it all back by the end of the next week!
Anyhow, there wasn't much on the web about it so maybe I have it wrong. But unless it is something you can live with forever, I don't think there is much hope for long term success.... Because you are RIGHT, it is about lifestyle change!
Sorry I couldn't be more positive.............P