5D-D600-D800

Unless you re-did you testing from yesterday's thread already (which you may have, so please correct me if I'm wrong), you left out the part where you had AF delay turned on with the Nikon, and used some of Nikon's slower focusing lenses but a 70-200/4 L on the 5DM3 :-).  It's misleading.  Those are absolutely critical points that dramatically affect AF performance of the D600.    Its like racing 2 similar cars, but giving one bald tires, and coming to the conclusion the one with new tires was way better.  Maybe not the best analogy, but you get the point.

I caution anyone who looks at Nikon vs anything else AF tests to confirm AF delay is turned OFF (it defaults ON) and directly equivalent lenses are used before coming to any conclusions about AF, one way or the other.  I think it's silly they leave that setting on by default, but they do.