@Steve: thanks for your input. That's more or less how I feel.
]]>Should I delete the question, as it is (probably) impossible to get a satisfactory answer? Or should it just be closed, seeing that there are at least seven people who found the question interesting, and so perchance it ought to be preserved for posterity? For now I've voted to close the question as 'no longer relevant'. If some high-rep user is reading this and decide that it should be closed (as opposed to deleted), it would help if they can also add votes to close it.
(Mostly I want to close/delete it so that it doesn't pollute the front page by having an unanswerable question propping up every now and then by MathOverflow.)
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