To the Editor: As Congress considers legislation to reform the business model of the Postal Service, it must confront a basic choice: to permit the Postal Service to function more as a business does, or constrain it from doing so. With greater business model flexibility, the Postal Service can return to profitability and financial stability. A flexible business model would speed product and pricing decisions, enable a five-day per week delivery schedule, and permit the realignment of mail processing, delivery and retail networks to meet lower mail volumes. It would also allow the Postal …