You're right ... he's one of the 3 worst players with a minimum of 500 PAs over the last two years - he ranks right ahead of Panda and Alexei Ramirez, and behind such stalwarts as Cody Asche and Alexi Amarista.
So, in terms of WAR he most certainly is. Add to that his inability to steal bases, hit or play even consistent defense (consistently bad doesn't count), he actually is as awful as we believe him to be.
Well, when you put that many qualifiers on it. This kind of analysis really shows the limits of just posting WAR and having that be the only conclusion.
The fact that he got over 500 PAs shows he far from the top 5 worst. He was certainly overexposed, but if he was hidden a little more and played to his strengths, his WAR counting stats would have been less negative. If he only had 300 PAs, that would not have made him "better" but by this standard he would have been significantly better.
I am interested to see him in a limited role and see what he can produce, now that he has no other options.