Was Babin the best free-agent signing?

Over at the AFC South blog, Paul Kuharsky has a post that says the Texans' Johnathan Joseph was the most valuable free-agent signing of this past offseason. Surely, the transformation of the Texans' defense is a big part of the reason for their division title, and Joseph was a big part of that transformation.

But if you disagree with the choice, there's a SportsNation poll in Paul's post that allows you to vote for someone besides Joseph as the best 2011 free-agent signing. Other choices include New Orleans running back Darren Sproles, Tennessee quarterback Matt Hasselbeck, Denver running back Willis McGahee and Philadelphia Eagles defensive end Jason Babin.

What's interesting about this is that none of these guys was projected to have the impact he has had, while bigger-name signings have had far less impact. I guess that's the way it always works, but it got me thinking.

Babin was clearly the best free-agent signing in our division, the best of many by the Eagles, who likely imagined ballyhooed cornerback Nnamdi Asomugha would top their list. Asomugha has played fine, for the most part, but has had some memorable negative moments in his first season in Philadelphia. Babin, meanwhile, ranks among the league leaders in sacks and has made it clear that his first season as a dominant NFL pass-rusher (2010, in Tennessee) was no fluke.

So Asomugha was supposed to be the Eagles' best free-agent signing, but Babin actually was. How about our other three teams? Let's take a look:

Dallas Cowboys

Then: The biggest deal was to lock up left tackle Doug Free before he hit the market, and the Cowboys did. But Free has been a disappointment and could be moving back to right tackle next season as impressive rookie Tyron Smith moves over to the left side. Free-agent safeties Abram Elam and Gerald Sensabaugh have had their moments but are part of a struggling secondary.

Now: The Cowboys' best signing turned out to be wide receiver Laurent Robinson, who has 797 yards and nine touchdowns on 50 catches. He answered the team's preseason questions about the No. 3 receiver spot and was a more-than-adequate replacement for Miles Austin during Austin's many injury problems.

New York Giants

Then: The Giants eschewed external free-agent pursuits because of the importance of signing their own. At the time, the highest priority was running back Ahmad Bradshaw, who has played well on either side of the foot injury that cut out the middle of his season. Center David Baas has been a bit of a disappointment in his first year in New York.

Now: When the Giants re-signed defensive end Mathias Kiwanuka and said they would be moving him to linebacker, it seemed like a desperate move from a team that had very little behind its defensive line. But Kiwanuka has been a major stabilizing force for the Giants at his new position, and he still moves up to rush the passer with his old defensive line buddies on third downs.

Washington Redskins

Then: The Redskins made a big splash when they signed defensive tackle Barry Cofield away from the Giants and made him a nose tackle for the first time in his career. Cofield has played well, but it took him a while to adjust to his new position. A year from now, this will look like their best 2011 signing from a list that includes Santana Moss, Donte' Stallworth and yes, Rex Grossman.

Now: The Redskins signed safety O.J. Atogwe just before the lockout -- a move a lot of people almost forgot they made once free agency began in earnest. He's had some injury problems, but when he's been on the field, Atogwe's been an impact player, as has cornerback Josh Wilson, whom they signed away from Baltimore.