D800 is within factory standard! Needs +20 to stop it front focusing.

I would be very hesitant to send them a lens.  You may be right, but I would be very hesitant.  Nikon has there own lenses in the shop that are presumably adjusted properly. They don't need a lens from the customer.  If all of my lenses need maximum AF fine tune value it is unlikely to be my lenses.

So what I see happening is that you send in one lens, Nikon techs, in their infinite wisdom, end up tuning the lens to work with the camera, ignores the camera issue, and sends it all back "fixed".  What if you have a second body?  Now you have a lens that is out of calibration for the other body.  Plus, it does nothing for all the other lenses you own.

Like I said, you may have a point there of sending in a lens.  But I wouldn't do it.

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Mike Dawson