Moodys Investors Service this week warned of increasing complexity in the structures of new jumbo MBS. However, losses on the deals will only occur in low probability scenarios and issuers have yet to bring back all of the non-agency MBS features seen before the financial crisis. Moodys said complex cash-flow structures in new jumbo MBS can increase risks on senior bonds in the event of high mortgage losses. The features include super-senior support bonds, exchangeable securities, principal-only bonds, and pool interest-only bonds. These securities pose...