This request originated via recent discussions on HN, and the forming of HARC! at YC Research. I'll be around for most of the day today (though the early evening).
I personally vouch that this isn't fake. (But anyone familiar with Alan's work could tell that just from reading his comments here—who could possibly fake these?)
In this kind of cases you can send an emails to the mods hn@ycombinator.com . Most of the times dang replies very soon. (And if the story is a fake, they'd usually remove it from the front page.)
HN has always worked informally. We don't have 'processes'; it isn't clear that we need them, and the thought of having to set them up makes my soul cry. But anyone who has concerns about fakes, abuses, and the like can always get an answer by emailing hn@ycombinator.com. We appreciate such emails because occasionally they point out actual abuses that we need to take care of!
This is assuming the real one wouldn't have articulated anything unique and contextually valuable. (Unless you've got some sure-fire method to determine which statements are objectively so and that's what's getting confused.)