Someone did a stylometry attack against hn awhile ago, it would with very high confidence unmask alt accounts on this site. It worked. There is zero reason to believe that it couldn't be applied on a grand scale.
That sounds considerably more narrow than what the GP described.
What if I don't have an alternate HN account? Or what if I do have one, but it has barely any posts? How can you tie this account back to my identity?
Stylometry.net is down now, so it's hard to make any arguments about its effectiveness. There are fundamental limitations in the amount of information your writing style reveals.
I don't know about the original post being referenced, but the ground truth could be known to good approximation. I assume HN has a good idea of which accounts are the same person using IPs, and could actually evaluate the false negative rate.
