Linebacker Patrick Willis quickly figured out why NFL teams historically have had trouble avenging a Super Bowl defeat when he began perusing the 49ers' upcoming schedule.San Francisco 49ers linebacker Patrick Willis runs drills during NFL football minicamp at the team's training facility in Santa Clara, Calif., Wednesday, June 12, 2013.Patrick WillisPatrick Willis: He'll try to help the 49ers do what no team has done since the Miami Dolphins in 1973: win the Super Bowl a year after losing in the Super Bowl. His perfect attendance at offseason workouts is a good start.