And what gets me, is that original screenshot was a 5D TWO vs. a D800...not 5D3. Or that's how I read it when I looked again, I could be wrong. Either way, I don't care. I've lifted my own little camera's files 2 or 3 stops with less noise than that, and at higher ISO. The end result isn't perfect, but it's usable.
I can't imagine doing 5 stops worth of negative compensation on anything, nor having the need or desire to. It's interesting to look at and talk about for an hour...but not for days. How often do you need to include a diffuse sky with the sun in it?
Most of the time, the sun is either more hidden than that by clouds, or fully out in a clear sky, or not even in the shot. In all those cases, you sure wouldn't waste time underexposing by 5 stops at ISO 100. What other shots need that much DR? Like where race car headlights are shining directly into the lens at sunset? Nobody cares.
In the summer here, even the same sky would be blown out worse, if you attempted to do the same thing. 5 stops wouldn't be enough. Has anyone in the USA noticed, that on a bright sunny day in winter time, there is about half as much light as there is on a bright sunny day in June? In June, it almost seems like the sun gets brighter each year. I can't imagine how bright it is closer to the equator. One day I'll find out, haha.
I just like looking at pretty pictures!