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I agree with Kittyk
A couple more things to consider.
1) The image you take with the D800 system has to be sharp down to the pixel level to see this difference. It could be limited by other factors already such as vibration/technique blur, motion blur, not best lens used, diffraction (too small an aperture), or comparing points in print not in the plane of focus. Note that being within the standard calculations of DOF is insufficient for this fine a detail. Standard DOF measurements on a FF sensor assume an acceptable blur of .03mm or 30 microns. This is already 6 times larger than the D800 pixel size - ergo the true portions of the image with the extra sharpness is a much narrower distance range around the plane of focus.
2) Depends on the resolution of your printer. A d700 already maxes out what a 300 dpi printer can do for 8x10 image. You would need either a higher dpi printer (effective dpi not their ink drop size) or a larger print to see the difference.
3) Even with a higher dpi printer, the average eye has limited acuity in a similar range.
Bottom line if you get an image that meets all the factors in #1, IMHO
for 8x10 - you won't see a difference
for 10x14 - with careful observation you can see a difference
for 16 x 20 and viewing at 10 inches or closer you will tell the difference.
I think the biggest limiter is taken images with an approach/technique to get a good image where you would be able to see a difference (e..g #1)