A brief explanation as to how winning an auction in Free Agency might mean you have successfully overestimated the value of the player.
http://www.advancednflstats.com/2010...rn-out-so.html
Dungy covered the other side of this after the game with Costas while talking about the Eagles struggles on defense. And this is the same topic Thompson covers when asked. That the free agent (Asomugha was the topic), despite a veteran's grasp of the nuances of the League, will still struggle to fit into your schemes and personnel compared to a lesser regarded, but homegrown player.
This article also covers why a specific player (say a pass rushing, fast OLB) that seems to be a perfect match for a team (3-4 D) still gets overrated by the winning bidder, unless the synergy (the article's word for the match) is tremendously high. But those kinds of matches are limited by the nature of an auction and the limited supply of prospects.
And in an almost word for word explanation of what many suspect about Thompson's bids, the author covers why a successful bidder will actually shave their bid and the worst performers will plow on with their original value.