In '07, the Pats played the final 2 games to win, not to rest the starters. As a fan, I said throughout that season that I'd rather have them win the Super Bowl than go 16-0 in the regular season and lose.
OTOH, one risk of resting key players is getting stale, and in football, there are almost as many injuries in practice (though not to QBs) as there are in games.
A few weeks ago, I thought despite W-L records, the Vikings were the best team, but right now I think that's the Chargers. I'm not convinced the Saints or the Colts are big favorites. The Colts could've lost 3 games before this weekend, and the Saints have dominated exactly one team in the last 6 weeks
As for me, I almost didn't care if some other team went 16-0 this year and won the Super Bowl just to shut up Mercury Morris.
In the Colts' case - now they have to win it all or their fans will crucify them.