Most Oiler fans I have seen have placed him solidly in the bottom pairing since even prior to the lockout.
Whitney has not been good for 2 years now. It's a shame, because for his first year or so in Edmonton he was a beast.
I don't think it is all injury related. I think he has lost any semblance of confidence he had and just can't get back into the mind set he needs to be in. It's not just that he is slow, its that he is making poor reads defensively and offensively.
I wouldn't be surprised if he goes to another team and manages to regain some of his lost form.
The Edmonton Oilers have a history of this occurring/players wanting out. Can't put my finger on it.