of course, there are some people who have success with juice fasting. To be honest, however, I know some people personally - including my wife - who have tried the same without getting any other results than feeling hungry and being frustrated in the end. I think, it is also depending on your genes and on the kind of job you are doing. My wife has quite a busy job, so she couldn't concentrate on her work and bear the stress while fasting. Finally, she quit the fast and shifted to dietary supplements.
So, from my personal experience I would not recommend anybody to fast while having a busy time. Though, however, I do acknowledge that some people might be really successful with juice-fasting, but maybe that's not the kind of diet everybody is able to go through.