Check out the team audit for AZ over at Baseball Prospectus. It does generally concur with my assessment yesterday, that our pitching has been the problem. We've had good or better production from most positions, except shortstop, catcher and center field.
SS has been mediocre; catcher is not surprising given Hill and Snyder basically are replacement players. Center Field will hopefully be better taken care of in future than by Cruz + McCracken. [Though have you noticed how Cruz has been playing for the Dodgers, since signing for them after Boston dumped him, after we dumped him? In 23 games, he's batting .304]
On the pitching side, however... Of the twenty-four pitchers used, only six have a positive VORP (Value Over Replacement Player) more than 1.5 - four starters and two relievers. Thirteen pitchers have a negative value, meaning basically, that we'd have been better off using a AAA call-up.
Of course, in a lot of these cases, they were AAA players, or equivalent thereof (waiver wire dumps, etc.), but they also include Russ Ortiz, Mike Koplove and Randy Choate. We're paying that trio almost $10m this year, and to realise we'd likely have received better performances from a randomly-selected Tucson Sidewinder is...disappointing.