There were two times in the season - the 43-3 annihilation of Atlanta and 56-14 annihilation of Washington - when the Cowboys played well enough to beat ANY team in the league. They were at their A+ level. Nobody - not the Chiefs, Pack, Rams or Bengals - could have stopped that version of the Boys.
So, clearly, the Cowboys were capable of a Super Bowl champion level of play. The problem is, they did it only about 10% of the time.
How do you coax that sort of performance level out of the team more often? You don't even have to do it 100% of the time - a team like the 1992 Cowboys, for instance, still had their shares of bloopers and were only playing at that level maybe 70% of the time. But that was good enough to get Lombardis.