Thank you all for your valuable input 👍.
There's another reason why the back shows more signs of wear and it is, simply, that there is a lot more white space than on the front.
I agree that this doesn't even qualify as EF. It's VF+ at best indeed. Beside the obvious folds, not one of the corners is even close to being sharp!! This should have been easy! PMG gives “3” for population in AU50. At best it should be “2”, and I certainly would like to have a look at those two other notes! I can't believe they both be so incompetently graded.
What's the saying? “Buy the note, not the holder”, right? This is a textbook example.
EDIT — On the front, the middle horizontal fold is clearly visible. If you look under the “ℓ” of Commonweaℓth at the bottom of the central text, too, the fold that is so obvious on the back can be seen here, too, extending from the ℓ to the white frame.
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