Standard & Poor’s and Fitch Ratings have announced separate ratings of two new non-agency MBS over the past two weeks, making a little noise in the long slumbering non-agency MBS market. Fitch this week released a presale report on Redwood Trust’s next prime jumbo transaction, while S&P rated a securitization of seasoned subprime mortgages that drew flak because it got higher grades than the agency gave the U.S. government. The new Redwood transaction, Sequoia Mortgage Trust 2011-2, looks a lot like the company’s last issuance back in February. It’s backed by $375 million of squeaky-clean prime jumbo mortgages, most of which were originated by...