+1. My 7D was worse on ISO 640 and above than my 5Dc is at ISO 1600. I haven't done any comparisons, but I think my 50D might be cleaner in high ISOs than my 7D.
And the fact that scientifically reproducible tests say you're wrong do not impact your opinion one bit, eh?
It's a good guess your opinion was formed by zooming straight to 100% which means 18 MP magnified > 15 MP magnified > 12 MP.
Another good guess is that if you had to pick from unlabeled screen or print views...equal in size...you would pick the 5Dc image as the noisy one that "must be the 7D."
First of all, read my post first- I said both 5D (FF) and 50D (APS-C) that I have used appeared less noisy than my 7D. So it has nothing to do with confirmation bias. Also I say 'my 7D' which was noisy. I loved it for everything else, but I have complained about the noise several times on these forums before I switched to the 5D III. Was my 7D out of spec? I think not- I have heard of similar noise issues from many people.
Secondly, your first guess is wrong- I don't pixel peep when looking for noise. When I say, ISO xxx was unacceptable it means I looked at it full screen on my 24" monitor and it looked bad. That's a pretty low bar, wouldn't you say?
Thirdly, your second guess is irrelevant- what matters is data. I am pretty confident I will do far better than chance in picking out my 7D images at high ISO (large size jpegs, at least). If I care enough, I can post some of them from my 7D and I think you might agree.
Finally, please don't go mentioning "scientifically reproducible tests" without citing them. As it is, comparing high ISO images from single copies of two cameras side by side don't comprise scientific tests as far as I am concerned. Show me something like what Roger Cicala does, and I will hear you.