Teams YPPA Pass Freq.
The average YPPA on first down in the NFL last year was 6.63 and the average pass frequency on first down was 46.9%. So there are some good teams (Jets, Chargers, Vikings) and some average teams (Tennessee, Denver) but no really bad teams. One potential interpretation of this data is that efficient passing is the key and as long as a team can pass efficiently, then the run/pass mix is not that important. An alternative interpretation though is that if teams passed more frequently, they would have performed even better.
Looking carefully at the teams though, the motivation for the low Pass Freq. can be understood for most of the teams. The Ravens, Broncos, Jets and Tennessee all had young and/or unproven QBs at the helm so that play callers would naturally tend to not give them as many attempts as Manning/Brady/Breese. In Minnesota, Favre's age and the presence of a premier RB (true for the Titan's as well) seem to make a clear case for a lower first down passing frequency.
Finally, we get to the Chargers. Here is the team with the highest YPPA on this list and 8th in the league, but they throw on only 43% of first down attempts. They had one of the best QBs in the game running the show and no dominant RB. Now they finished with 13 wins so it is hard to argue that they underperformed, except that they lost again in the playoffs and it is this conservative play calling that is at the heart of why. My prediction model had the Jets over the Chargers largely because the Chargers were downplaying their best weapon.
My son is a huge Chargers fan (and dismissed my prediction of a Jets win last season with a flipant "well your wrong"), so I hop that Norv and the boys who are calling the plays in San Diego will learn that their conservative ways will only lead them to the same place over and over again.