I concede immediately that I'm oversimplifying the issue. Google doesn't keep the "problem" Santorum result at the top of the SERP simply because they don't like Rick Santorum.
They're also (perhaps mostly) doing it to keep themselves out of the news, since the prevailing meme about that SERP now is "oh well, that's how the Internet works" and the result of a manual intervention would be a flood of news stories about an intervention Google probably doesn't want everyone knowing they do regularly.
They're also (perhaps mostly) doing it to keep themselves out of the news, since the prevailing meme about that SERP now is "oh well, that's how the Internet works" and the result of a manual intervention would be a flood of news stories about an intervention Google probably doesn't want everyone knowing they do regularly.