2.5% is not 2.5 lbs. Take what weight you're working at and multiply it by 2.5% and add that much weight.
Point is if you don't have the calories to build muscle, then you're lacking the materials for growth. You're over worrying about all this. Eat, work hard, rest when needed, and be patient; the rest will take care of itself.
If you spend too much time worrying about each program and boucing around, you'll never really get started and your progress will be slow and stale. It's a good program; start working it.