At what point is it OK to accept an NFL team as being "for real?" Four games? That's a quarter of the regular season, the equivalent of 41 games in baseball. Were we still dismissing the Tigers as an out-and-out fluke after 41 games last June? (And if you were, it's time to reassess.)
How about six games? That's more than a third of the season and plenty of time for every team to have faced at least one rough-and-tumble matchup that was capable of exposing it for a fraud. Chicago has walked over some patsies on its way to 5-0, but it topped a solid division rival on the road in Minnesota and destroyed Seattle, the reigning NFC champs. The undefeated Colts have had some trouble with also-rans (the Titans and Jets) but dispatched playoff-caliber opponents in the Jags and Giants.