How much responsibility? I'd say much less than 50%.
Personally, I think the guy has done an excellent job of restocking the roster given where it was at season's end 2012.
And whatever responsibility Keim may have had in deciding WHO to bring him, I don't think he had much to do with the amount paid to some of the questionable free agent talent that was brought in.
He has done exactly the right thing in signing almost every free agent to a ONE year prove-it contract with minimal bonus money. The previous regime threw buckets of money at career underachievers like Adam Synder and Terrence Holt or injury-risks like Al Johnson or Travis Laboy.
NFL Network's Albert Breer was on with M.J. a few days ago and claimed there was serious doubt whether the Cardinals could even retain Keim. Make no mistake about it, he is viewed very favorably in NFL circles and I feel he's off to a good start in restocking the roster.
Not every FA acquistion will pan out. But with the quantity of new talent added, some will. And those that don't are gone at season's end with little or no salary cap impact. That is a 100% improvement from the Whisenhunt-Graves regime's Pittsburgh West mentality and overpaying questionable or over-aged players.
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Mike Sando: Good luck evaluating the job Keim has done since hiring on with the Cardinals in 1999. He's been the team's vice president of player personnel most recently, but lots of people have contributed to the player evaluation process in Arizona over the years.
http://espn.go.com/blog/nfcwest/post/_/id/87956/a-few-thoughts-on-keim-as-cardinals-gm