Sure, if Brett was a slam dunk I would say sign him and make sure you get his ring size. But at almost 40 years of age, he's not. In fact the only guarantee with Brett is that he will turn the locker room into a circus show.
Childress already took his chances this year by drafting WR Percy Harvin and Tackle Phil Loadholt. With a team set to win now, why take more chances with an over-the-hill QB?
Even if the Vikings had not made a move all offseason, they still would've been picked to win the division.
Needing help at probably the most important position on the field, many fans cried for a Pro Bowl QB (myself included). I would have to say though that Childress understood this need just as much as anyone else. But instead of throwing all of his draft picks at the one position, he build a strong supporting cast to fill in the few offensive holes.
So with the addition of solid backup QB Sage Rosenfels, playmaking WR Harvin and a 6'8" tackle that eats DT's for breakfast, I would say mission accomplished.
Favre shmarve. The Vikings are going deep into the playoffs this year with or without him.