As we've hit the midway point of the 2012 regular season, Shutdown Corner thought it would be a good time to take a look at the free agent additions (or retentions) that have turned out to be bargains, and those that have turned out to be busts. We began this two-part series with a look at those free agent deals that have worked out well . Now it's time for a look at the free agent signings that, thus far, haven't panned out. Mario Williams and Mark Anderson, defensive ends, Buffalo Bills : To help improve a pass rush that ranked near the bottom of the league in 2011 with just 29 sacks, the Bills stormed out and made Williams the highest-paid defensive player in NFL history, signing him to a six-year, $96 million contract that included $50 million in guaranteed money that included a $19 million signing bonus and $5.9 million base salary for the 2012 season. Overall, Williams will take home $25 million this season and, at the midway point of the season, it's hard to argue that the Bills are getting great return on their investment. Williams hasn't missed a game and is playing in over 85 percent of the team's defensive snaps. In that time, Williams has 23 tackles, 4.5 sacks and one pass defensed. However, nearly half of Williams' sack total came against an Arizona Cardinals offensive line that has allowed a league-high 41 sacks already this season (no other team has allowed 30 sacks). Williams did the first seven games of the season with a torn ligament in his wrist , and had a sack in his first game after undergoing surgery during the bye week, so the potential is certainly there for Williams to turn things around in the second half of the season. Anderson was coming off an impressive 10-sack season with the New England Patriots, so the Bills augmented the signing of Williams by inking Anderson to a four-year, $19.5 million contract that included $7.9 million in guarantees, $8 million in cash in 2012 and up to $2 million in annual incentives ($8 million total) tied mainly to sacks. Anderson had one sack in nearly 250 snaps over the first five weeks of the season before suffering a left knee injury that required surgery — and quite possibly requires another "procedure" before we see him on the field again — those incentives probably won't be a factor in 2012. Stanford Routt, cornerback, Kansas City Chiefs : Prior to the unrestricted free agent signing period, the Chiefs braced for the departure of Brandon Carr by signing Routt, who had been released by the Oakland Raiders for financial reasons (specifically to avoid a $5 million base salary guarantee), to a three-year, $18 contract on Feb. 21. Routt's deal included $6 million in cash for the 2012 season, comprised of a $4 million roster bonus, $200,000 workout bonus and $1.8 million base salary. Routt started the first seven games of the season, but was inactive last Thursday night against the San Diego Chargers and was placed on waivers earlier this week. As a vested veteran, Routt could file for termination pay, which means he could receive the $847,059 that remained on his salary with the Chiefs. In case you were wondering, Carr's five-year, $50.1 million contract with the Dallas Cowboys paid out $11.2 million this season.

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