The collapse of MF Global can be traced back to the myth that Goldman Sachs (GS) produces the best risk takers, according to industry buzz. The mantra at MF Global: "Ratchet up the risk. Let us Goldman guys fix this." Ex-employees say Jon Corzine's cozy relationship with risk traces back to his Goldman days. The man himself on risk: "You can’t achieve the kinds of returns we want just by buying on the bid and selling on the offer."