You're boiling things down to one incident, but Favre's interception was partially a result of poor play-calling and a really dumb penalty to give away, which forced his throw. And there were the fumbles. Similarly, Manning's interception isn't why they lost the game per se, the onside kick gamble that paid off, Brees' completion rate and the sterling work of the New Orleans defence were all big factors.

This wasn't a Superbowl where a team lost the game, New Orleans won it.