Most big-box retailers and supermarket chains would prefer that debit card transactions disintermediate the predominantly signature-based Visa and Mastercard networks for predominantly PIN-based regional networks led by Star, Nyce, Pulse, and Accel. PIN-based networks save merchants pennies per transaction. Until this month, Visa had a policy that inhibited merchants from asking cardholders to use PINs, whether through prompts on a POS terminal or the suggestion of a sales clerk. Visa has modified that policy following recently issued clarifications from the Federal Reserve Board regarding ...