Caldwell's limited statistical impact

Joe Flacco and the Ravens' offense struggled this year under Jim Caldwell. AP Photo/Patrick Semansky

On Tuesday, the Detroit Lions announced Jim Caldwell as their 26th head coach -- and the fourth since 2003. Caldwell's offensive background and head-coaching experience were intriguing to a Lions team that was searching for someone to help a talented but inconsistent Matthew Stafford. But when we consider that Caldwell earned a lot of his credentials working with the legendary Peyton Manning, the question has to be asked: Is Caldwell as good as the numbers indicate?

From 2002-2008, Caldwell was quarterbacks coach (and eventual assistant head coach) for the Colts, helping Manning win three MVP awards. Then he took over in 2009 and led the Colts to a Super Bowl. But was Caldwell's success in Indianapolis circumstantial?