The members of the cuckoo's nest known as Packer Nation would be better off expending their psychosis on the whereabouts of running back Ryan Grant than former quarterback Brett Favre.

Grant was the Packers' most effective offensive weapon and the NFC's best runner for the second half of the 2007 season. General Manager Ted Thompson has chosen to low-ball him horrendously, in a much more egregious use of power than anything that's taken place in the front office's dealings with Favre.

Grant remains without a contract. The Packers have a viable replacement for Favre in Aaron Rodgers, but no such option at running back.

We're supposed to be worked up over here about the possibility that Favre will be in Mankato some time next week as the Vikings' new quarterback.

Certainly, there would be devilish delight to see the suffering of the Green Bay zealots if this were to take place, but how much would this increase the chances of the Vikings returning to the Super Bowl for the first time in 32 years?

Put it at 17.5 percent, rather than 15 percent with Tarvaris Jackson as the quarterback.

We should be able to admit this on both sides of the border: Favre's play over the past six seasons rates out as high mediocrity.

There's a tendency to say this trend started with the wild-card-round loss to Atlanta after the 2002 season. Actually, the team around Favre was better than him during that 12-4 season, and then he singlehandedly led the Packers to their first-ever playoff loss in Lambeau Field. He had an abysmal 54.4 quarterback rating in that 27-7 loss.

Since then, he was solid in 2003 and 2004, woeful in 2005 and 2006, and very good statistically in 2007. As Favre increased his touchdowns (28) and reduced his interceptions (15) last season, much credit went to second-year coach Mike McCarthy for his ability to massage the playcalling and reduce the quarterback's high-risk throws.

Hearing that conversation last fall was similar to the way the Vikings talked about offensive coordinator Scott Linehan's work with Daunte Culpepper before the 2004 season. Culpepper was operating with a subpar offensive line, yet he followed those intense Linehan tutorials by throwing 39 touchdowns and a mere 11 interceptions.

Culpepper also went into Green Bay and badly outplayed Favre in a 31-17 wild-card victory. Culpepper threw for four touchdowns, and Favre countered with four interceptions.

A year ago, Favre led the Packers to regular-season victories over the New York Giants, Denver, Kansas City, San Diego, Carolina, Oakland, Detroit twice and the Vikings twice. He was so-so in a victory over St. Louis, and the Packers defeated Philadelphia and Washington in spite of him.

The Packers had a walkover against the Seattle Chokehawks in the playoff opener, and then Favre was a frozen loser against the underdog Giants in the NFC title game.

He'll turn 39 on Oct. 10. He hasn't worked seriously at his craft for seven months, while Jackson and Rodgers both have spent 100 days on the field or in meetings getting ready to arrive as competent quarterbacks in 2008.

Favre? Over the past half-dozen seasons, he has been a top 10 quarterback three times (2003, 2004 and 2007), a competent QB once (2002) and incompetent twice (2005 and 2006). Going back to the loss to Michael Vick and the Falcons, he's 2-4 in playoff games with seven touchdowns and 12 interceptions.

What you would be getting here, ye prideful Purple, would be an old and unprepared quarterback who had lost a helpful adviser in McCarthy, much as Culpepper lost Linehan after the 2004 season.

There's ample evidence in two seasons of NFC North competition that McCarthy is much sharper in designing and getting execution from an offense than are his rivals to the west. Favre might have pals in Minnesota, but he would miss McCarthy's brainstorming.

The Vikings are looking at a minimum of 10 victories with a healthy and improving Jackson as their quarterback. They would be looking at a maximum of 11 victories with an aged, erratic Favre, and that's what they would be getting.

He's not worth the fuss -- except to ESPN and the NFL, which truly would appreciate the all-time-record ratings were Favre to arrive at Lambeau in Purple on Sept. 8.

If that happens, I like the Packers by 10.

Patrick Reusse can be heard weekdays on AM-1500 KSTP at 6:45 and 7:45 a.m. and 4:40 p.m. • preusse@startribune.com