Baltimore proving that this has been a pretty solid trend over the years:
Post Super Bowl Coma: It's an established fact that last year's Super Bowl winner will generally suck in the early going of the current season. Betting against them in weeks 1-4 would have given you an 18-5-1 record since 1995. (Includes 2-1-1 last year). A team that looked awesome in its Super Bowl win (and most do), leaves a lasting impression in the minds of the betting public. The linesmakers know that and as such they compensate (with the line). Further, everybody and his grandmother is gunning for last year's Super Bowl winner. If you are a mediocre team and can take down last year's winner early in the season, it's a feather in your cap, a boost to your morale, and perhaps a positive portent of things to come!