"Any given Sunday" is not parity. There IS parity this year, but the Circle Of Fail is meaningless. There's about eight teams that all have legitimate shots at the title, almost all of whom have some flaw. None of these teams is heads-and-shoulders better than the others.
Pats
Ravens
Houston
Giants
Bears
Packers
Falcons
San Fran
*maybe* the Broncos
That's parity, *not* the fact that Kansas City somehow managed a win against the Saints so you could complete your circle-jerk. I'd wager you could complete that circle if you looked at most NFL seasons.