I called AppleCare Tech support just asking (out of curiosity) if the Mid 2012 model Macbook Pro's need calibrating, and the lady on the phone said YES. I thought these Macbook Pro's don't need calibration? I gave her my Serial Number so it was obvious what model I had (to eliminate misunderstanding).
And in calibration, I mean battery calibration.
And in calibration, I mean battery calibration.