These so-called web gurus seem to be good at one thing - selling you crap.
Any relevant critique of the clip - which I find very informative. Or just flagging your state of denial?
I'm not sure how what I said has any reflection on the topic of the video (as you stated correctly in your first sentence). I was commenting on the many so-called experts on the web that seem to keep popping up all the time. Yes, you could say that's hypocritical as I often offer advice here on CR, but I don't claim to be an expert, I have examples to support what I say, and most importantly, I'm not selling anything.
Since you asked, however, I'm not in any irrational state of denial and yes, the D810 has a better sensor, I think that's a fact (#1). Despite the fabulous sensor, it didn't sell as well as Nikon had hoped, primarily because of the competition from the 5DIII (fact #2). Nikon upgraded several aspects of the camera to make it more competitive with the 5DIII (fact #3). Some feel they have succeeded, some don't (fact #4).
My opinion: setting aside the 1D III and D600 fiascoes, respectively, I don't think you can go wrong with any recent Canon or Nikon models, and choice should be based on individual budget, needs, and current lens/system investment. If I were a Nikon shooter, I would be elated by the D810 and D4s and would likely own those instead of the 5DIII and 1D X. I have a considerable amount of money in Canon glass, find that Canon meets or exceeds my current needs, and prefer the ergonomics of Canon, so that's what I own (fact #5). If I truly NEEDED, not just DESIRED to have more megapixels and/or DR, I'm sure I would make the switch (fact #6).