Youk has always taken some abuse for being something of a sour sort. However Youk has sacrificed a good deal for this team. Youk should have rightfully stayed at first base for his career. He would have been a gold glove first baseman, would have stayed healthier and would have extended his time as a top level player. Instead the Sox, never satisfied with taking an A grade defender and leaving him at his position, moved him to third. True Youk could play 3rd well but it was not in his best interest to make that move. Youk has never balked once, never complained once and gets basically no credit for it.
I think much of his "decline" can be attributed to his having a somewhat brittle body and having been exposed by the move to third.
At least Youk has made some progress since coming back of the DL. He is at least back to making good plate appearances again. He may never reach his peak again but I also think the Sox are as much to blame for that as anybody.