Yeah, he's a good player, when he's healthy; like you said. But, he hasn't been healthy in 3 years. What makes you think a 35 year old player is going to all of a sudden become healthy after not, in such a long time?
Granted, Middlebrooks is kind of in the same situation. But he is also a hell of a lot younger. The upside is a lot more than a 35 year old catcher who hasn't had a good season in three years.