diberry - 4:21 pm on Dec 13, 2012 (gmt 0)
IOW: They 'get stuck' in the 'test mode' of the algo for some reason.
This makes sense. Because there are only two plausible theories I can buy at this point, knowing what we know, and one is that this is all some form of testing (which, as you point out, may be functioning in a way that makes sense to machine learning rather than humans).
The other theory is that Google is trying to push certain people to buy Adsense, and we'd need more evidence to reach that conclusion. I mean, there's no ROI in them for just targeting Backdraft7 and a few other people in hopes they will notice, care and elect to buy advertising from Google rather than other sources. It would have to be more widespread... or maybe there would be a pattern if we looked at how many ads pop up on zombie queries, or something like that.