It's an excellent program. If you fear you are too out of shape, don't worry about it. You don't have to do all the reps at once. You'll improve with each week. The biggest thing is having the right weights or resistance bands available for when you workout.
Personally, I dropped from 42 pants to 36 pants in the 3 months I was on it. Great results. I've fallen off the wagon since and am back in my 38's, but I am slowly getting back into the swing.
When things don't go your way, stop and think, "Problem, or inconvenience?" - with apologies to Robert Fulghum