I think you make a good point. Defenses are more sophisticated, and the league has some great passers (the Mannings, Brady, Rodgers, Rivers, Brees, Schaub, Stafford, etc.), and tight-ends that are more receivers than blockers. Therefore, defenses are playing more nickle and dime, and drafting more pass rushers and defensive backs. There is really no way to make a good comparison. Marino's year was incredible, as is Brees's year.