In my humble opinion, a coach (or anyone, really) should be evaluated primarily in his area(s) of strength.  I would never expect Chris Kluwe to convert every bad snap into a completed pass, just as I would not shun a free agent slugger from a baseball team for not being able to bunt well.  Since Brad Childress had been touted as an offensive genius and a quarterback guru from his tenure with the Philadelphia Eagles (as QB coach and offensive coordinator), anyone should be able to look at his track record and make a solid case for him (if the information matches the hype) or against him.

The best information, then, is Donovan McNabb's performance at various times in his career and the Eagles' offensive ranks pre- and post-Childress (excluding his first year in Philadelphia when Donovan McNabb only started 6 games as a rookie).

A similar argument can be made that Gus Frerotte and Brad Johnson also performed worse than their career averages under Childress (2006 was Johnson's career-worst rating), although some or most of that could be attributed to age.  In any case, Brad Childress has been responsible for the offensive performance (or at least the QB performance) with significant input regarding personnel and scouting decisions, offensive schemes and philosophies, and playcalling over the past 7+ years, even if he wasn't making 100% of the decisions himself.

Not that passer rating is everything, but it does tell us a story in Donovan McNabb's and Brad Childress's cases: In 2004, McNabb posted the highest rating of his career (with T.O. and Childress); however, 2006, 2007, and 2008 are his next 3 best ratings (without Childress, and with 2 receivers that Childress had either traded away for Billy Freakin' McMullen or passed on in the draft in 2008).

Donovan McNabb has also completed 60% of his passes since Childress left Philadelphia.  2004 was the only Childress year in which he completed 60+% of his passes.

In terms of TD:INT ratio, McNabb has achieved 2:1 or better 6x in his 9 full seasons of starting in the NFL.  One of those years was 2004, and 3 of them were 2006-2008.  In other words 100% of the time without Childress and only 50% with Childress, counting the T.O. year (less than 50% if excluding the T.O. year).

How have the Eagles and Vikings ranked offensiveely since 2000?  (Passing yards and net yards per passing attempt are bolded to make the table more readable and to highlight his area of supposed specialty.)

Year: Pts, TotOffYds, 1stD, PassYds, NetYds/Att, RushYds, Yds/Att

while QB guru:
2000: 12, 17, 17, 20, 26, 15, 4
2001: 9, 17, 27, 20, 20, 14, 8
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while OC:
2002: 4, 10, 18, 19, 18, 7, 8
2003: 11, 18, 13, 20, 20, 9, 5
2004: 8, 9, 14, 7, 8, 24, 10
2005: 18, 19, 21, 8, 19, 28, 17
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Eagles free (at last) of Childress:
2006: 6, 2, 9, 3, 3, 11, 5
2007: 17, 6, 5, 10, 16, 8, 2
2008: 6, 9, 8, 6, 12, 22, 24
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Vikings under Childress:
2006: 26, 23, 26, 18, 26, 16, 14
2007: 15, 13, 19, 28, 19, 1, 1
2008: 12, 17, 18, 25, 18, 5, 6

As all not named Brad Childress or Zygi WIlf can see, the Eagles were never above average in both passing categories without T.O. while Childress was in Philly.  Although Childress was touted as being knowledgeable of passing offenses, Childress's most productive offenses featured strong rushing attacks (at least in yards per attempt) and not very efficient passing games.  The Childress era Vikings have yet to sniff the median as a passing offense despite bringing in veterans like Bobby Wade, Visanthe Shiancoe and Bernard Berrian.  Yes, there is a small trend of improvement, and 18,18 would be somewhat close to the median (and his offense has not performed that well in Minnesota), but an offensive genius and QB guru should not need to hang his hat on almost being an average passing after 3 years.

By contrast, the Eagles have been 17th (median is 16.5 or 16 and 17) or better in ALL categories--with the exception of 2008's rushing ranks--in each season  since being rid of Brad Childress.  Overall, the Eagles have been a top 10 offense in all 3 categories all 3 years, and they only ranked that high twice while he was there (only in the Year of T.O. while he was OC).  The Vikings have yet to crack the top 10 in points, total offensive yards, or first downs.  Even with the league's best rushing offense, Childress and Bevell could not figure out how to take advantage of 8 in the box or score a few points by being less than 90% predictable to crack the top 10 overall.  Were it not for one of the best rushing defenses in the league, the Vikings could muster no more than 6 wins per year in the Childress era.

And as if all of this weren't enough, the 2005 Eagles were the worst (25th) in giveaways during the Andy Reid era (lower numbers are better, ranking 1st meaning fewest giveaways).  Zygi and the Vikings couldn't wait to hire him despite that.

Just what is the basis for Brad Childress's reputation as an offensive genius and QB guru, I wonder?

It should finally materialize this year.  Not only should the Viking offense be at or above the median in most categories, but it should also rank 12th or better overall since 12 teams make the playoffs (and we want to be a real playoff team which can compete in the postseason rather than a one-and-done).  The Vikings were in the playoffs in 2008 (with the 3rd highest payroll) and in 2005 (with the 9th highest payroll under Mike Tice).  The 2009 Vikings are 2nd in payroll (so far), and the last 2 times Brad Childress coached such a team were in 2006 (6-10) and in 2004 (lost the Super Bowl).  Maybe he had too much talent on those teams to work his magic, whatever that could be.

The Vikings should be real contenders to win the Super Bowl XLIV, and Brad Childress should be fired if they are not.