First off, I'm going to assure you that yes, a Fat Fast is a great plateau-buster. You can use a one, two, or three-day fat fast to make up for indiscretions on a carb-up, kick-start a new fat-loss challenge, or get yourself into ketosis when you've had trouble getting there.
That said... I'm doubting a fat fast is really what you need. It might be a fun way to jump-start your next phase of fat loss, but the fat won't continue peeling off until you tighten down the diet. Here's a recipe to restart your fat loss.
1. Go ahead and do a fat fast, but only for 2 days. The goal here is to get your body into ketosis as fast as possible, and the Fat Fast does that. It's not part of MANS, but it's very effective. There's a list of foods, and some details on the Fat Fast (Dr. Atkins New Diet Revolution has this, too) at
http://www.low-carb.com/atarfatfa.html .
2. After the first two days, keep your carb count down under 30g per day again. You're running 50-65g/day right now, and clearly that isn't working for you. As your body fat drops, you can expect to continue to have to make adjustments to your diet. This may (will) eventually include *increasing* your carb count as you approach your ideal weight, but for now, you've bumped up against what Dr. Atkins called your "CCLM": Critical Carbohydrate Level for Maintenance. You maintain weight at 50-65g of carb per day. Drop it and your losses will resume.
3. Don't carb up for a few weeks. Skipping a carb-up keeps your body in fat-burning mode longer, and can often overcome some metabolic resistance. I didn't carb up for four months (except a couple of days on holidays) while reducing 50 pounds of body fat and putting on around 15 pounds of muscle. I was -- and am -- a total newbie lifter, though. You're around 30% body fat right now; you're not going to lose much (if any) muscle by skipping the carb-ups for a few more percentage points.
That's actually my general advice on MANS. Prioritizing muscle gain? Carb-up. Prioritizing fat loss? Skip the carb-ups. Mark McManus just put out a new version of Total Six-Pack Abs that walks through smart carb-ups on a cutting diet, but it requires much more careful management than MANS.
4. Once you start carbing up again, strive to make them cleaner and/or shorter. Brown rice and oatmeal are much better choices than pizza and sweetened cold cereal from a box. Dropping your carb-up from 2 days to 1 day makes a big difference for us fat guys, too. 2 days is just a little too long for someone who's addicted to carbs like me.
Try those four tips for a week or two; I bet you your fat loss will resume like normal. Expect to hit these little plateaus every few months, though, and you'll need to create a new plan and execute it one more time.
MEMAR: Measure, Experiment, Measure, Adjust, Repeat.
--Matt B.