Well, that's the prob with different tests, you don't know whether you can compare them. At least you can compare different lenses tested under the same conditions. But then there is also the big issue of lens-variation and sloppy quality control...
In my opinion the PopPhoto-test doesn't show border-quality as an extra and that is something I wouldn't want to miss, as pronounced deterioration of sharpness towards the borders/corners could put me off buying a lens. See my review of the Tamron 11-18mm
: that lens was quite good at the centre but the borders looked really ugly.
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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