One of the most important issues for mortgage lenders and homebuyers alike in the whole qualified mortgage/risk-retention/ability-to-repay debate is how much legal liability lenders will have over the mortgages they originate in the Dodd-Frank era. For policymakers, one of the biggest decisions they will have to make to bring certainty to that question is which legal standard to impose, a “rebuttable presumption” or a “safe harbor.” …