Since I have already said that I see little value in such resolution comparisons, while you apparently care a lot, I suggest that you search around: DPreview is far from the only or best DSLR testing site on the internet.
It's standard practice in academic circles to always quote your sources. If you don't care about an issue, why raise the matter in the first instance or engage in debate?
I am struck by your pre-emptive speculation that these other sites are using flawed methodolgy while your often highly critical approach to some data and testing methods seems to have overlooked the various potential flaws of the DPReview methodology discussed in the DPReview forums.
Which other sites are you referring to? I always start from the premise that methodology possibly could be flawed, especially when I attempt tests myself. It is true, however, that sites such as Dpreview with a reputation for a meticulous and consistent approach, tend to generate less skepticism regarding sound methodology than do unknown, unspecified or rumoured sources.
If you truly care about methodology and seeking to measure such small differences in resolution, here is a nit-picking point. DPReview did the E-3 resolution testing with the 50mm f/2 lens at f/6.3, an aperture shown in testing elsewhere to be not the sharpest available. (That lens is good enough that the resolution keeps improving down to about f/2.8, and indeed most 4/3 lenses are sharper at f/4 than f/6.3). So the resolution measurements are held back somewhat by lens limitations; specifically diffraction due to using a smaller than optimal aperture diameter.
That's a good point. At face value, it does seem that dpreview might have blundered here. When sharpness (or resolution) is an issue, why not use both lenses at their sharpest aperture. In this situation, perhaps it would have been fairer to use the Olympus 50/2 at f2.8 and the Canon 50/1.4 at f4. PhotoZone tests show that the Canon 50/1.4 peaks in sharpness at F4, at least in the centre at MTF 50.
Checking the review again, I find the following statement from Dpreview.
For direct comparisons we always use sharp prime lenses stopped down, typically to F9 for 35 mm lenses and F6.3 for Four Thirds lenses. Here we have used the Minolta 50mm F1.4, Pentax 50 mm F1.4, Olympus 50 mm F2.0 Macro, and Canon EF 50 mm F1.4.
Perhaps the reason for using F9 with the 40D and F6.3 with the E-3 is for the sake of consistent results across the frame, from edge to edge. One can only speculate on the degree to which the Olympus 50/2 might be sharper at f2.8 than it is at f6.3. But it's clear from the Photozone tests that the Canon 50/1.4 is definitely sharper at F4 than it would be at f9, (assuming that centre sharpness at F9 would be marginally less, or no better than at F8. They don't show the results for F9).
Nevertheless, if I had been carrying out these tests myself, suspecting that the Olympus 50/2 might be sharpest at f2.8, I would have taken some more shots of the test target at wider apertures to see if that made a difference to the RAW image comparisons. Perhaps Simon Joinson actually did that, just as he also used Olympus Studio 2. I notice that Dpreview are now branching out into lens reviews.