I think this could be better summed up as a guide to maintaining uninterrupted service during a DDoS. Which is only something you do in the first place if you run the numbers and find that being down would cost you more in lost revenue than staying up would cost you in temporary overprovisioning. It's another of those "a solution to a problem that only really exists at Amazon/Google/Facebook scale" whitepapers, except in this case the relevant "scale" is economic, not technical.