NORMAN, Okla. — Oklahoma’s last four national championship teams have featured stat-stuffing offenses and nearly impenetrable defenses. The Barry Switzer–led squads that won back-to-back titles in 1974 and ’75 and a third in 1985 punished opponents with the Wishbone offense, a devastating option-based attack that took whatever it wanted on the ground. While less schematically iconic, the defenses on those teams, led by the Selmon brothers (Lucious, Dewey and Lee Roy) in the mid-’70s and by All-America linebacker Brian Bosworth in ’85, were units to be feared. Bob Stoops’s lone national title came from a team that scored 37 points per game and allowed just 14.