Your being rather misleading. This is what the article says:
I am not being misleading. IR does not specify what "highest quality" DR means, nor do they provide images to demonstrate. You and I both know the threshold is arbitrary and the result would be impacted by NR and processing (as you just demonstrated with the infamous D800 / 5D3 test above).
I am not exactly certain how they do these tests or how they are calculating dynamic range,
They are photographing a step wedge and feeding it to Imatest. Preprocessing would change the result for "highest quality", but the total is pretty much the total. Again we're crossing the line from discussing DR to actually discussing shadow latitude.
but they are pretty clear that when it comes down to QUALITY
Which they neither define in real world terms nor illustrate with real world samples, so it's pointless to debate.
Even at low, the 70D scored 11.7 stops, and at medium it was 10.8. Those numbers seem more in line with what other sites measure.
What other sites? DPReview only does JPEG now, not ACR best, and DxO doesn't agree either way. (You can't cherry pick the "high" setting for Canon and the "low" setting for Nikon.)
I've worked with Canon, Nikon, and Sony RAWs and I can tell you with certainty that there is not a 2 stop difference in DR. They both fade to white and black at about the same points. What is different is how far you can push shadows due to noise vs. the work you want to put into the processing. Even with work if you push hard the final result is better with Exmor. But it doesn't matter nearly as often as Exmor fans pretend, especially in print (vs. pixel peeping).