Having looked at a few more tests at various apertures, it's clear the 26mp sensor provides a substantial improvement in detail at F8, as expected, compared with the upressed 5D crop at F8.
At F22, I have to admit that, even after applying a bit of additional sharpening to the interpolated 5D image, the 40D image looks better, slightly finer grained and perhaps even has a greater 3D effect, although I'm still doubtful if such subtleties would be noticed in a normal size print of, say, 22"x33".
A 100% crop of a 26mp image on this laptop represents a print size of about 5 feet by 3 1/2 feet.
Here's the F8 comparison, followed by the F22 comparison with the interpolated 5D crop sharpened 100% at pixel radius 0.8.
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