>Jacque and Brian have valid points. If you had some >additional lenses or another body to test, it would probably >be more definitive. But, with only one body and two lenses >it's speculative. Perhaps you could borrow a body and another >lens or two and run some tests.
Since I don't have access to more bodies and/or lenses, I'll just request an exchange of the lens. I'm betting it's the lens b/c I shot 2 other lenses (24-85 and 70-300) without any autofocus adjustments (didn't have FoCal at the time) and they were very acceptable. Granted, that's not an apples to apples comparison since neither can goto f/2.8 so it's DOF wasn't that thin. The 70-200 also looked great, -3 just looked that little bit better.
It's the 24-70 that completely out of the norm, so I'm guessing, bad sample. If the other comes in and it is also -16 or around there, then I'm not going to worry about it. My D800's left focus is just dandy and I don't want to mess with the body since I've already been through 2 others to find this one.