As Clayton notes, the Cardinals wouldn't need Kolb to become a top-flight quarterback to make the trade work. They would simply need him to be much better than the quarterback play they received from Derek Anderson, Max Hall and John Skelton last season. Even decent play from the position last season would have put the Cardinals over the top within the division, in my view.
Arizona played the easiest schedule in the league over the second half of the season. Close losses to Tampa Bay, Minnesota and Carolina could have turned out differently with even average quarterback play. I've cautioned against playing the what-if game without also converting some close victories into defeats, but in this case, Arizona would have been better positioned to win those games as well.
The question isn't so much whether the Cardinals should make a move for Kolb. They need to acquire a quarterback, whether it's Kolb or someone else. The question is what to pay for a mostly unproven passer.
Last year, the Cardinals ducked out of the Charlie Whitehurst trade talks. Is Kolb another Whitehurst? Unlike Whitehurst, who had never been a No. 2 quarterback, Kolb has started games. He has served as the backup and he was good enough, at one point, for the Eagles to name him their starter heading into a season.
Clayton also touches on Seattle as an option for Kolb, though he thinks Arizona has more to gain because the Seahawks could get similar play by re-signing Matt Hasselbeck. How much should an NFC West team give up for Kolb? Hit the ballot box.