On one side of the street, the guys go to work in hard hats and construction boots. On the other, Larry Mahoney’s pushing flashy neckties, custom suits and $700 smoking jackets at the Andover Shop in Cambridge, Massachusetts. This is the stark contrast now dividing Holyoke Street. For the past couple years, Harvard University has been building The Richard A. and Susan F. Smith Campus Center, a brand new gleaming building in the heart of Harvard Square. “They should have been more upfront about the length and duration,” said Mahoney, the long time manager of the Andover Shop.