Hey, maybe it has to do more with the team that does the signing, as opposed to signing a good deal of FAs. The Redskins have been the winners in free agency the last several years, and their talent evaluation, cap management, and draft techniques are all faulty. The Pats signed something like 21 free agents before the '01 Super Bowl season. How'd that work out for them that year?
The difference with the Pats methods are that they have the money to spend, they are targeting areas that they needed to improve, and have done so with good players. The only questionable signing, in my mind, is Stallworth, because of the ability of him to play in this offensive system. Thomas was signed to a relatively cap friendly deal and his versatility is perfect for how BB likes to use his LBs, Brady is a replacement role player at a reasonable price, Morris was signed for just over a million a year and Welker was signed to a 5 year 18 million dollar deal, nothing outrageous (draft compensation may have been a little pricey). They are not over the top signings, and are all fits for what the Pats needs were and are Patriots players.