The real error here is that people are viewing this as a one-year project. It isn't. It can't be. What Marv is doing is getting some depth with upside. The problem with Buffalo has been, among other things, crappy depth. That was the problem with the D-line last year. ZERO depth. And as much as I loved Sam Adams, he was only worth a minimum of snaps per game. If you tried to rely on the guy through the season to be a cornerstone of your team he would be worthless.
The most important FA move the Bills have made this year is to attempt to keep Nate. That is huge. The second most important is cutting ties with MW. That was extremely important. Also, Lawyer just wasn't worth the $$ he was getting.
A 10 mil cap figure for Moulds is just silly. He isn't worth it, as much as I like him. If he lowered his salary by 2 mil it would be worth it, but he won't. Hell, many people could afford a much nicer car, but then you wouldn't be able to live in a nice house. That's the rationale you have to address this with.
Another thing that people fail to realize is that it is difficult to move around in the draft unless you have the cap flexibility to do it. Maybe Marv is planning to package a few picks to get another #1? Maybe he's going to trade his two #3 picks to get another #2. This has a huge impact on what you want to do with your cap.
Regarding the escalation of the cap, I don't think what they have done is a problem. We've got over 10 mil worth of dead money this year which will be gone next year (MW, Lawyer, and Moulds).