Mostly unrecruited out of Fork Union Military Academy, the 6-foot-7, 306-pound Anthony Castonzo became the first true freshman in a decade to start on the offensive line for Boston College. After being moved to left tackle as a sophomore, Castonzo playing right tackle in 2007, earning All-Freshman and All-Atlantic Coast Conference honors during Matt Ryan’s final season at BC despite being undersized at 250 pounds. If it seems like the Illinois native is being hard on himself for allowing just one sack in 650 snaps last season, consider that the projected first-round 2011 NFL draft pick and Rhodes Scholar candidate who hopes to conduct cancer research one day also missed only nine blocks in 13 games last season. “I’d hang my hat on it more if it had been zero,” Castonzo said. “I’m upset with myself if I don’t give up zero sacks. My top goal is that nobody