I actually agree with TJ up to a point. I'd like to get into the "excuses" part of it, but first I'll say that Fitz wouldn't even be worth that amount of money even if he were producing at the top of his game. WR's don't take teams to SB's. Even Jerry Rice doesn't take those teams to SB's without Montana and Young (along with all the HOFers on both offense and defense). Even Megatron with a better QB than ours doesn't take his team to the SB. It just doesn't happen.
What I really wanted to look at was the so-called excuses people make for his lack of production last year. I'm only talking about this past year, if ya'll want to keep arguing about QB's that's another argument entirely (and further enhances the point that no WR in history is worth that kind of money). I don't think Fitz had hammy or lack of separation issues because of age. For one thing, as Duckjake continually points out, Fitz is relatively slow and has always been relatively slow. Even with Warner it's not like he had uber separation in those playoffs where he smoked everyone. He was catching it in a crowd of 2 or 3 guys. That's what he does, so let's stop arguing that his age is making him slow--he's always been somewhat slow.
Regarding the hammy issues: I think that's more a product of how he was being used than an indication of age. He was running a lot more shorter, crisper-cutting routes, lining up all over the field, and cutting often-times in directions opposite to the direction he's used to cutting. Furthermore, he was blocking more than I've ever seen him block. By far. To do that you have to continually plant and basically do lunges with your hips, even on a whimpy block that isn't effective. He did both those things all year long. I'm not saying he never blocked before, but certainly not as much as he did this past year and certainly not near the line of scrimmage, around the tackles, like he did this year, many times picking up linebackers and safeties. Those two things combined--the different route trees and excessive blocking at the line of scrimmage--will wear on anyone's hammy's. I had also read his route trees had break-off points depending on the defensive scheme, sometimes breaking off upfield, sometimes continuing perpendicular to the line of scrimmage, which Fitz said was new to him (it's similar to the route tree's the Pats use in that respect). All of that combined will take a toll if you aren't used to being used that way. He still manned up and played injured and continued his blocking assignments.
Having said all that no WR is worth that kind of money, regardless of how he was playing. What I don't think is cool though, is the people who had little problem with his contract until we got decent again this past year. When he was the main guy putting butts in seats it was okay, because everyone was making bank off him, but now that he isn't the sole reason for it the contract needs to be tore up.