Overrated can also apply to players that are good but not great. Sitton is a great pass blocking guard but he's nowhere near as good in the run game. I believe he's judged mostly on how he is vs. the pass which makes him overrated if you're judging him on the whole.
Lang has improved. He's been very far from a great G for us over the years. Perhaps,he is ascending to it but he hasn't been great.
We have two solid guards one of which is a great pass blocker.
Ted Thompson sits on his hands per former GM: "because they’ve had 25 fricking years of great quarterbacks. Of course it works. Try it without a special quarterback."