This "alternate possibility" is one that came to my mind when I thought about this. Of course one could try to verify it.

And anyway - now, I understand that this is beside the point you are making now; just returning to the context set by the article - let me stress that I still fail to see how this is a problem.

It would be very simple to "fix" the scoring in this regard, all it takes is to disable voting in questions older than 30 days, for example. But I'm stumped on how SO would benefit from such a move.

Quite the opposite - this would be an obvious incentive for repeating oneself (or others); reposting old explanations to keep on scoring points off the same know-how. Plus time-wasting fights on what is and what is not a duplicate, etc.