If you want stability, you can't do worse than to become an offensive coordinator in the NFL. Fruit flies in high school biology labs last longer on the job.
Consider this: By the time training camp for the 2012 season starts this summer, 23 of 32 offensive coordinators will have been on the job less than 18 months. If it takes two seasons for a quarterback and his play-caller to fully mine the depths of a playbook, 70 percent of the league could be referencing the Cliff's Notes version. The dean of offensive coordinators? That would be Marty Mornhinweg of the Philadelphia Eagles, who's held down the job since 10 games into the 2006 season, has called plays for five different starting quarterbacks in that time, and interviewed for a head-coaching job less than two weeks ago.
Take this knowledge, pair it with the fact that it's a quarterback-driven league where a 5,000-yard, 41-touchdown season didn't even merit a Pro Bowl invite, and you realize why the narrative exists: Great quarterbacks make great play-callers, not the other way around. Look at Tom Brady; in 2012 he'll work with his fifth different play-caller in a continually evolving offense, and he's as good as ever.
So when fans learn that Sam Bradford, an exceptional talent off to a rocky start in his NFL career, is about to get his third offensive coordinator in three years, they might be encouraged. The kid could use another set of eyes. He's struggling -- call in a specialist!
Convention says it can't hurt. Reality says it could be a disaster.