CDOs and the subprime mortgage crisis have some analogues to pre-Enlightenment darkness in human intellectual history. The idea that authoritative figures can use maths to give junk debt the midas touch is basically financial alchemy.

There was no sound reasoning behind it. It was literally just "maths is really powerful, and these people are the Smartest Guys in the Room, which is not really that much different from "these guys are really Holy, and also the Smartest Guys in the Room" in previous generations of humanity. Just market it with Math, and you can defraud the most powerful and prosperous society in history.