On the ninth floor of McDermott, Will & Emery LLP’s downtown satellite office, rows and rows of attorneys comb through documents at 99 computer consoles. They form the backbone of National Review Services, an expanded discovery service that McDermott said can cut discovery costs by up to 85 percent in matters such as commercial, antitrust and patent litigation. “The group was formed about three years ago after a number of partners at McDermott shared frustrations about the e-discovery process on a …