I've kind of thought that that may be a thing too. The Super Bowl seems like only yesterday, and it is only human nature to have a tough time ratcheting it all the way back up again. It's almost like they're still in their refractory period.
That said, the purging of Harvin from the locker room in combination with increased roles for young energetic dudes like Richardson, Norwood, Turbin, Michael, Helfet and Willson could really help.
It was an ugly game, but a beautiful win. That game winner, breaking tackles, plunging into the endzone TD by Willson really could be a seminal moment of rejuvenation. A close win with that many mistakes really shouldn't feel as good and meaningful as this does. With the Willson TD and the Irvin sacks you could just feel the juice being re-injected into the squad. Wouldn't shock me if a few straight opponents get blown off the field by the Hawks in the following weeks.