If you haven’t seen it yet: We reported on Friday that Sen. Dick Durbin, D-Ill., proposed allowing the Postal Service to “pilot” 5-day mail delivery in a few areas around the country. Polls usually indicate that the public is okay with 5-day delivery; Durbin wants to see if those poll numbers hold up when the idea becomes a reality. One other item I wanted to highlight from that hearing (at which John Potter, the Postmaster General, was one of the witnesses). Sen. Susan Collins, R-Maine, said several times that she’s worried 5-day delivery will reduce mail volume. At one point, she…