Cynthia, I have done a grand total of two workouts, but I've been working on nutrition first (baby steps for me). I have read and understand the concept pretty well. The basic premise is that you need 6 separate workouts a week: three "resistance training" which is not quite strength training. It is mostly bodyweight exercises and yes, they will make you very aware of your muscles and they really do only take about 15 minutes. The other three are "intervals." This is a different approach to the "you must elevate your HR for 30 minutes" type of cardio, but I know from experience with body for life that it WORKS. You have to establish a scale of 1-10 where 1 is "I'm sitting on the couch doing nothing" and 10 is "I'm going to die if I keep doing this, it's so hard." With her intervals, you start out warming up at a 3-4 for a few minutes, then elevate to a higher level (intro is a level 5-6, I think?) for a minute, then back down to a 3-4 for a minute. You repeat the last two steps 3-4 times for a cycle of 15 minutes, then cool down for about 2-3 minutes. With the warm up and cool down, the session should be about 20 mintues total. There are various ways to work the workouts into your day/week, including doing both workouts every other day, doing one workout every day for 6 days, then resting a day, and a bunch more.
Also, there are 4 levels of workouts included: introductory (4 weeks), Basic (4 weeks), Intermediate (4 weeks) and Advanced (4 weeks). I'm satisfied that it's not going to be something my body gets used to and it stops working, as happens when you do the same workout over and over again, KWIM?
And I only bought the $40 e-book, not the whole shebang $150 or so setup (goodness knows, I've spent enough money on fitness plans...I didn't want to spend another $150!). So far I'm quite happy with it and feel like the 16 week workout plan alone was worth the $40. It did take me a while to work through the e-book...I think it could be written more coherently, or it may just be that I was reading it on the computer screen and couldn't flip back and forth. But that would be my only complaint.