Apparently both pl;ayers thought it was a solid investment in the future as well since its their signatures on the contract, and they deposited their signing bonus checks into their bank accounts.
And if both players want to be paid fair market value every single season, then only sign short term deals, because getting fair market value in every year of your long term deal is impossible, even Haynesworth wont be getting paid fair market value in year 3,4, or 5 of his deal.
Players have two options - get the huge money of fair market deals by signing short term (where you will make way more money over the life of your career if you stay healthy), or the security of long term deals and the big signing bonus check. Players cant have it both ways, but it doesnt stop them and their agents from trying and nine times out of 10 failing at that plan.