Since I've shot scenes like that and not had a problem: pictures or it didn't happen.
I'm sick of words. I'm sick of opinions. I'm sick of theorizing. I'm sick of people misremembering underexposure tests as "real world normal exposure and there was banding!"
Pics or it didn't happen. If I was a mod it would be: pics or you are banned for a week
Since you claim all of these things are possible, why don't you lead from the front and show us how it is done?
Where are your pictures showing that Canon doesn't have a problem with keeping highlights and shadows?
Lots of people saying Canon's cameras can't do it and you're insisting that they can.
Quick and dirty screenshot comparison: http://s28.postimg.org/6t5fhmhe5/7d_dr.jpg
Crop at 50% with additional LCE in PS: http://s7.postimg.org/oli4obisr/7d_dr_2.jpg
+1 exp and +80 shadows. This equates to +2.5 exp (I matched using just the exp slider to be sure), but if you do it that way you lose the sky.
For sky: -60 highlights which recovers the same highlight detail as -0.5 exp (again I checked with just the exp slider to be sure).
NR was L35 and C50. You can just start to pick up a bit of color splotching at 100%, and of course the 7D can be a bit 'grity' at 100%, but at 16x24" I do not believe that would ever be a problem.
I did process/print a 2 exposure blend of the same scene. But the reason was not due to noise but due to superior tonality/fine detail in the shadows. You get superior tonality/fine detail by blending on Exmor as well. I certainly would have been happy with the single frame version had I not had 2 exposures to blend.
I certainly do not see a 'problem' with Canon's highlight/shadow retention here, and this is the first generation of their 18 MP crop sensor.
Again, Exmor is better. If I ever order an A7 I'll put the time in to do a proper, side by side test. If I order a 7D2 at the same time then I can do old crop, new crop, FF, and Exmor FF. Having had the chance to test shoot Nikon and Sony Exmor bodies I know from experience Exmor will be better in shadow latitude.
But I also know from experience that a real world test will not show the drama difference that you get when severely underexposing and/or turning off all NR. The differences are simply not worth all the words the DRoners have posted in this forum. Canon sensors can handle the majority of contrasty scenes just fine. And the difference between being forced to HDR with Canon and forced to HDR with Exmor is much smaller then the DRoners would have anyone believe.