As we continue to pound the table about the effects central bank asset purchases are having on market liquidity, it’s nice to know that there are at least a handful of people out there who agree that maybe — just maybe — depriving the market of high quality collateral by monetizing everything that’s not tied down could serve to destabilize markets and may indeed introduce systemic risk. The list of those speaking out on the issue has grown with the size of central bank balance sheets and has recently come to include SEC officials, BoJ officials, and investment banks.