Can a cleanse taste good, and do you need it?

Walking into Arianna Huffington's house for the book party for Kathy Freston's Quantum Wellness Cleanse, I was slighty worried that we might be met with waiters bearing trays of lemon juice and cayenne pepper. No -- wrong cleanse! I was reassured to find out that Freston's Quantum Wellness Cleanse: The 21-Day Essential Guide to Healing Your Mind, Body and Spirit, famously practiced by Oprah, doesn't involve fasting, which I consider potentially unhealthy. The Brentwood house was filled with beautiful and Hollywoodish people like Jeff Katzenberg, Jim Wiatt, Tom Freston and Dr. Dean Ornish mingling and munching. Many of the guests, more accustomed to steaks at the Grill, had never encountered seitan before. "It's like tofu, only kind of different," explained a tall blonde who works on the "Millionaire Matchmaker" show. Serves You Right catering, which normally does omnivorous spreads for the top agent crowd, did a nice job going all vegan with seitan satay (yes, I know it's not tofu), spring rolls, tofu "tartare" crackers and petite red velvet cupcakes. (Sorry, but without cream cheese frosting, what's the point?) Anyway, on the Quantum Cleanse, you basically give up alcohol, animal products, caffeine, sugar, gluten and animal products for 21 days, and according to Freston, you'll feel amazingly good. Having just polished off two trays of pork dumplings and beef tendon soup at Dean Sin World at lunch, I was kind of feeling in need of some cleansing. Freston says that even if you can't do 21 days, you can help save the planet and your meat-riddled cells by taking Mark Bittman's advice and going vegan before dinner, or one day a week. Well, it's a thought, anyway.
My first instinct is always to game the system, like what if you went vegan, but with caffeine or booze? Wouldn't that feel just as good?
Would you consider 21 days without "the five substances that are so toxic on the body," as Freston says?