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Best free-agent signing: Chiefs RB Thomas Jones
From a cost and productivity standpoint, this was a steal. The Jets think the 31-year-old Jones is slipping, but this workout warrior is coming off his best season with 1,402 rushing yards. Jones won’t be asked to carry as heavy a workload in Kansas City while paired with Jamaal Charles, a 1,100-yard rusher in 2009. Jones, who signed a two-year, $5 million contract, is one of several off season acquisitions who make the Chiefs a dark-horse playoff contender.
NFL offseason's biggest winners and losers - NFL News - FOX Sports on MSN

Now, they did say the Raiders had one of the best off seasons but the Chiefs being a playoff dark horse could be a mantra if we have a good training camp.