Yeah, I followed that when I first started out, but I didn't like trying to follow the specific regimen. Also, I wanted to add at my rate, not according to a formula. Each session, I set out to do what I did last session, and if I can, I do a little more. Also, I didnt really have a goal of doing 100 pushups, per se - I just wanted to do what I could and then slowly improve. What I kept, though, was the 3-day a week routine and also the idea of doing 5 sets, with the last set pushing my limits. That has worked really well for me.