When I did my post about "The Best Quarterback of All Time" back in September, I was not expecting to still be getting comments on it in December, but I am.
One thing that struck me in the comments was people claiming Brett Favre as the best of all time. But I don't even consider him the best Green Bay Packer quarterback. That would be Bart Starr.
Using the same criteria I used to determine the best quarterback of all time, Starr is very close to Favre, even considering the different eras in which they each played. Starr's numbers are on the left, with Favre's numbers as of last season:
Completion Percentage: 57.4% vs. 61.5%
Average Gain per Attempt: 7.85 vs. 7.04
Touchdown Percentage: 4.8% vs. 5.2%
Interception Percentage: 4.4% vs. 3.4%
NFL/Super Bowl Championships: 5 vs. 1
Average Rushing Yards per Carry: 5.3 vs. 3.5
Passer Rating: 80.5 vs. 86.0
Those are similar numbers considering the different passing nature of the eras involved. The yards per pass attempt explain a lot. In Starr's era, the passes were generally thrown farther than in the "west coast" era of Favre. This also explains why Favre's completion percentage was higher, although Starr's 57% completion percentage was the NFL career record when Starr retired. Finally, with Starr typically throwing the ball farther than Favre, Starr naturally threw more interceptions per attempt.
But for a true comparison on game management, let's add fumbles to interceptions per game. Favre turned the ball over 1.57 times per game. Starr turned the ball over 0.93 times per game.
But the number that stands out is the championships, where Starr holds a 5-1 advantage. Adding in the facts that Starr was a better runner and game manager than Favre, and Starr is clearly the better Packer quarterback.