Most of your reply was about DX in particular. I am just as interested in FX as DX, maybe somewhat more so depending on the particulars. And that was the thrust of the my comment.
You seem to be rationalizing the feature stripping of the D600 based on "market needs"...
It seems to me that the D300 and D700 were huge successes that put Nikon on the map and, for the first time, made them truly competitive against Canon. It was not until the D300/700 that my Canon friends started wistfully talking about trading in all their Canon gear for Nikon. And these are wildlife shooters, where Nikon to this day cannot compete with Canon's lens line. Actually it was the lenses that stopped them, but that is another matter.
I believe the reasoning was that Nikon provided features that no one ever fully met, head to head, which is why Nikon is in the market position they are in now.
If they take a "me too" attitude, which you are suggesting, I think they will ultimately end up back in the pack - where they will belong. The lead belongs to those with a vision and the D300/D700 body features, which are almost identical, was the vision that put them in the lead. And that has nothing to do with FX vs DX but a design and marketing philosophy that they have very obviously abandoned.
Just my take on things. There is a lot of religion and philosophy in this.
I also believe that the failure of the D800 to achieve 8fps in DX mode, where the bandwidth is demonstrably not a problem (less than the D600 in FX mode), followed by the feature spec on the D600, is an indication that Nikon plans to reserve 8fps for the $5K pro bodies, purely as price differentiation. They proved they could move an FX sized shutter at 8fps with the D700. That should be old news, and integral in the line now.
As I mentioned before, they probably price differentiated me out of a new body anytime soon. We'll see how many others feel the same way. But this is a well thought out abdication of the lead Nikon took with the D300/D700 generation.
I would like to know exactly how you shoot AF-C in Focus Priority mode and focus/recompose with a D7000. I'm sure there was no adjustment necessary moving to a D800 since that adds features (buttons), not take them away. The D800 does exactly what my $1600 camera bodies do.