Well, Penn State did win the National Championship against Dawgs in the Sugar Bowl. Back in the old days when they could match up the two best teams in the country.
Back in those days, conference champions received automatic bids to the major bowl games: the Southeastern Conference champion to the Sugar Bowl, the Big 8 champion to the Orange Bowl, and the Southwest Conference champion to the Cotton Bowl. The Big 10 and Pac-10 champions played in the Rose Bowl.
With that arrangement in place, an independent team always had the ability to see the rankings at the end of the season and then accept a bid to play the highest-ranked team in one of the major bowls (except the Rose Bowl, of course). So if Nebraska ended the season ranked #1 and Miami was #2 (or vice versa), then Miami would accept a bid to the Orange Bowl to ensure that they were playing for the national championship.
This also explains why there were so few Big 10 or Pac-10 national champions from that era. Since those conference champions had to play each other in the Rose Bowl no matter how good or bad the opponent was, they never had the opportunity to "force" a matchup against a #1 or #2 team. This cost Penn State a national title in 1994, when they finished the season undefeated and ranked #2 but were forced to play #12 Oregon in the Rose Bowl while #1 Nebraska and #3 Miami matched up in the Orange Bowl.