From the looks of folks around us, the dropout rate for conventional high carb/low cal diets is much higher than 25%. I wonder if that number is really representative of reality. I suspect that dropout rates for both diets to be in the neighborhood of 60% at least the first time around. Maybe higher. Drastic changes to eating habits isn't easy.
That said, your recipe for exercise looks good. I don't run (hurts too much) but I walk either on the treadmill or around my hilly neighborhood at least 4 times per week. I lift 2-3 times per week depending on what shift I'm working. And, lately, I've taken a closer look at what I eat. I use about 3400 calories per day to maintain my weight, which is somewhat higher than the 12-per-pound rate you cited. But, my metabolism is a little more high-strung than average. YMMV.