...after reading a lot of comments on how the D800 is so unforgiving, I can understand.
Here's an interesting article where a pro photographer says he has to keep his shutter speed at 3x the focal length (as opposed to the old rule of 1/length) because the D800 is so sharp it makes the tiniest blur more noticeable than in the film days.
The Nikon D800 and the Holy Trinity of Lenses by Valerio Trigari | STEVE HUFF PHOTOS