Hi Rhonda,
I've been "somersizing," or using the methods of food combining that this program espouses, for nearly eight months now, with very good success. I started it at about the same time that I re-dedicated myself to a serious exercise program, so frankly my weight-loss and fitness success so far is due in part to the fact that I workout very regularly. But as a veteran of the Atkins/Protein Power diets, and many other eating programs out there, I personally have found that "somersizing" is much more well-rounded, non-restrictive, realistic for my lifestyle and easy to follow than other programs I've tried.
What I like about it is that it encourages eating from all the food groups (I love bread and other carbs!), and that it eliminates only what I would consider "junk" food such as processed foods, sugar, white bread/white flour/white rice, etc. It also encourages eating tons of fruits and vegetables. And for me it offers great flexibility; if you want to focus on increasing your protein for any given period--be it for one meal, for the entire day or longer-- you can do that. If you're craving carbs, you can have those too, as long as they are whole-grain and wholesome. You just can't have fats/protein and carbs together. And you can follow it eating regular, everyday foods. (I've never even tried any of the recipes in her cookbooks, though some of them look delicious!)
In the eight months since I've been following this regiment, my weight went from 151 pounds to about 126 (I'm 5'3"). I'm extremely satisfied with this weight because I do a fair amount of weight-lifting (including Cathe!) and so have a pretty good amount of muscle. But my body has shed a lot of fat and feels very lean and strong. I have never had anywhere near this level of success on other eating regimens, even when I was exercising seriously.
Anyway, hope this is of some help. I was initially reluctant to respond to your question because diet/nutrition programs elicit such strong responses and emotions, both negative and positive, from people. Someone may well weigh in (no pun intended) with negative responses about why "somersizing" isn't a good idea, etc. But if anything, I've learned over the years that you have to find what works for you, and this has done it for me.
Hope this helps! Best of luck to you.