Judging by the comments, the primary fan reaction to Brett Favre's retirement reports is skepticism, but the second-most-prevalent reaction is that No. 4 may be setting up a situation wherein he rides in on a white horse to turn the Minnesota Vikings' struggling offense around in midseason and help salvage a Super Bowl run.
As entertaining as that mindset is, it is based on the faulty assumption that Minnesota's quarterbacking productivity will falter in the event they actually have to play without Favre. There is no denying that Favre is coming off the best season of his illustrious career (it was the first time his passer rating topped 100) but there are ample metric reasons to think that the Purple and Gold's passing game will not only be nowhere near as bad as some are suggesting it will be -- it may actually be nearly as good as it was last season, even without Favre.
Before you call me crazy for thinking that either Tarvaris Jackson or Sage Rosenfels can fill Favre's statistical shoes, check out some of the evidence that backs up this claim.
Let's start by noting the two areas in which Favre really excelled in 2009: yards per attempt (YPA) on vertical passes and bad-decision percentage rate. Favre posted an 11.7 YPA total on vertical throws (defined as aerials of 11 or more yards downfield), which was tied for 10th in the league.
As impressive as that statistical ranking is, it pales in comparison to Favre's bad-decision rate. A bad decision is defined as a play in which a quarterback makes an error with the ball that leads either to a turnover or a near-turnover (e.g. a dropped interception, a fumble that is recovered by the offense, etc.).
I have been tracking this metric since 2005 and, prior to the 2009 campaign, Favre was as bad as his gun-slinging reputation would indicate. His percentages were always near or above the 3 percent mark, which is just above the league median point -- and the benchmark for poor performance in this metric -- of 2.5.
He did a 180-degree turn in that statistic last season, as his 1.2 percent bad-decision mark was tied with Green Bay's Aaron Rodgers for the No. 1 ranking in the league.
Using the vertical pass YPA and bad-decision rates as baselines, let's take a look at how Jackson and Rosenfels have historically fared in these areas.
Rosenfels is the veteran, so we'll start with him. His largest single-season pass volume came in Houston during the 2007 season, when he threw 240 passes while filling in for the injured Matt Schaub.
Rosenfels posted a 10.9 vertical YPA that season, or a total that was less than a yard away from Favre's 11.7 mark in 2009. Pro-rate the eight-tenths of a yard of YPA difference over the course of, say, 154 vertical throws (Favre's total in this category last year) and it equals 123 yards.
In other words, if Rosenfels can perform as well for the Vikings in this area as he did for the Texans in 2007, Minnesota should barely see a dip in its vertical pass production. And that doesn't even take into account the 13.3 vertical YPA Rosenfels posted while filling in for Schaub in the 2008 season.
Rosenfels did not fare nearly as well in the bad-decision metric, as his 3.7 percent rate in 2007 was three times as high as Favre's pace in this category last season. That obviously forecasts an increase in interceptions, but how many more picks are we looking at?
If we assume a pass volume of about 550 throws (slightly more than Favre's 545 throws last season), Favre's 1.2 percent bad-decision rate would mean about seven mistakes that could potentially lead to a turnover. Rosenfels' 3.7 percent mark would mean about 21 potential giveaways.
Fourteen picks is a significant difference -- but not every bad decision throw ends up being picked off. The typical rates for how often erroneous aerials are intercepted vary, but in general, it is somewhere around 50 percent; apply that number here and it would mean four picks via mistakes for Favre versus 11 for Rosenfels.
A difference of seven interceptions isn't good -- but they wouldn't cripple the Vikings' offense (especially considering the production they should get out of Adrian Peterson). That total also assumes that Favre would have kept up his anomalous 2009 pace and that Rosenfels would not improve on his poor performance in this area.
Now let's look at Jackson. His largest pass volume also came in 2007 and it contained more than a few high points. The two most notable of these were his 11.8 medium pass (11-19 yards) YPA, which was the best in the league, and his 2.3 percent bad-decision rate (tied for ninth).
Jackson's weakest metric points that season were low deep (20-29 yards) and bomb (30-plus yards) YPA totals. Those totals kept his overall vertical YPA down to 9.3, but a lot of that was due to having to throw long passes to Troy Williamson and Robert Ferguson. If the 18 deep/bomb passes Jackson threw to those two underachievers were taken out, his vertical YPA would have jumped to 10.9 yards, or exactly the aforementioned pace set by Rosenfels that proved to be a more than acceptable metric substitute for Favre.
Put all of these numbers together and it means one thing: If the man from Kiln, Miss., tries to ride that white stallion into town a few weeks into the season, Brad Childress should tell Favre and the horse to both head back home because their services won't be needed.
"KC Joyner, ESPN Insider wrote: