"...flagship sports model."
This looks like fun.
Searching the Gear Sig thread, 282 people list "1D" in their entries, out of just over 2000. Of those people, I am sure a couple have listed something to the effect of a "wish list" or "used to own". So lets say 10% of those folks currently own a 1D.
Of those, I will bet maybe 25% can, in 10 seconds or less:
* change their AF tracking speed
* customize their fps
* Set the camera to spot meter on the selected AF point
* Switch their primary and secondary card write settings
* Find their #3 custom WB setting
* Disable ROF
* change their maximum burst settings
I could go on forever, but the point is this. Debating over a camera that most of us will never own, and if we do, will never use to its fullest capability, is kinda stupid. Leave that stuff to the folks at Pop Photo. Worrying about this stuff is a sure sign that you aren't taking enough pictures.
Nikon makes good cameras. Canon makes good cameras. I have never had a client insist on knowing which I shoot before they pay me. And if you don't get paid to do it, you should worry even less about it.