Division records at the halfway point...any trends?

In the NFL, there are very set patterns in the scheduling for each team - of their sixteen games, they get six against their three division rivals, home and away each; four against another division within their conference; four against another division in the opposite conference, and two against teams selected to match where they finished within their division the previous year (first place vs. first place, last vs. last, etc.). The schedules are as fair as they can be made; it's only those last two games that will differ for two teams within the same division. Seattle would play two first place teams and the Niners would play two second place teams, for example, but otherwise they play the exact same schedule: six games within the division, four against the four NFC East teams, and four against the AFC West teams.

But, the interdivision matchups are another story altogether. Some divisions, let's face it, are stronger than others, and it changes from year to year. We all thought the NFC East would be the "NFC Least" again this year - except that Philly and Dallas have been Tier A teams all season. We all figured the NFC West was hands down the strongest - take the Cardinals out (the Cardinals?) and they're .500 and falling.

So, how ARE the divisions doing against each other so far? Let's find out...

AFC NORTH)   22-13-1 overall >> 7-1-1 v NFC South, 6-3 v AFC South.
NFC WEST)      19-13-0 overall >> 7-3 v. NFC East, 5-4 v AFC West.
NFC NORTH)  18-15-0 overall >> 6-4 v. NFC South, 4-6 v AFC East.
AFC EAST)        18-16-0 overall >> 6-4 v. NFC North, 5-6 v AFC West.
NFC EAST)       18-16-0 overall >> 3-7 v. NFC West, 8-2 v AFC South.
AFC WEST)       16-17-0 overall >> 4-5 v. NFC West, 6-5 v. AFC East.

(And now, the weak sisters...)

AFC SOUTH)     13-22-0 overall>> 2-8 v. NFC East, 3-6 v. AFC North.
NFC SOUTH)     10-22-1 overall!!> 4-6 v. NFC North, 1-7-1 v. AFC North.

The two southern divisions are a combined twenty-one games under .500 at the midpoint of the season. Indianapolis (at 6-3) is the only team above .500 of the eight teams, which includes Atlanta (2-6), Tennessee (2-6), Tampa Bay (1-7), and Jacksonville (1-8). 

Must be the bad weather...