The Patriots open training camp on Thursday at Gillette Stadium. With all NFL clubs restricted to an 80-man roster -- down from a maximum of 86 -- the structure of training camps across the league is likely to be altered. For example, some clubs are holding fewer contact practices and two-a-day sessions, so players don't get worn down. While the rosters are reduced, and the practices might take on a different look, every club will be seeking answers to key questions. The Globe's Mike Reiss runs down his top camp story lines for the Patriots ...