You can't accuse a team that opens with Georgia Tech, Penn State, Michigan, and Michgan Stare on back to back weeks of not playing a challenging schedule.
Any team that schedules Army, Navy, and Air Force in the same year and tries to ride that to the national championship is not being serious.
Compare that to who USC chose as non-conference opponents, for example. Arkansas (SEC west champs) and Nebraska (Big 12 north champs).