What caused the Credit Crisis, wonk edition

The above tables are from my friend's aforementioned magnificent thesis. It's available publicly, I'm just waiting for permission to post it because it has personally identifiable information on it (which I can black out, but still).

The table summarizes significant results. I highly recommend reading closely.

(Most surprising finding? "No strong evidence that credit ratings were affected by the amount of fees brought by the CDO underwriter, [indicating that] Primary reasons for rating agency problems not associated with fee system." This has been harped on by a lot of pundits, but I've never seen anyone use data, and certainly not data as good as this...)