It does sound like an interesting concept if you are an athlete or a bodybuilder, but I don't think there are many of those on this forum, which is why I guess you don't get any replies. I see that Tom Coghill also recommends it as a way to come off a water fast: http://www.fasting.ws/juice-fasting/support/guilt-compulsive-eating
I'm not fasting at the moment, but maybe I'll try this later, as I am a protein type and I don't like to break a fast with fruit juice.
Perhaps you can post a question on Tom Coghill's site? He says that he answers them all.