[Update: and now there's a fifth discussion thread, which you should probably use in preference to this one. Later update: and a sixth -- in the discussion section, which is where these threads are living for now on. Also: tag for HP threads in the main section, and tag for HP threads in the discussion section.]
The third discussion thread is above 500 comments now, just like the others, so it's time for a new one. Predecessors: one, two, three. For anyone who's been on Mars and doesn't know what this is about: it's Eliezer's remarkable Harry Potter fanfic.
Spoiler warning and helpful suggestion (copied from those in the earlier threads):
Spoiler Warning: this thread contains unrot13'd spoilers for Harry Potter and the Methods of Rationality up to the current chapter and for the original Harry Potter series. Please continue to use rot13 for spoilers to other works of fiction, or if you have insider knowledge of future chapters of Harry Potter and the Methods of Rationality.
A suggestion: mention at the top of your comment which chapter you're commenting on, or what chapter you're up to, so that people can understand the context of your comment even after more chapters have been posted. This can also help people avoid reading spoilers for a new chapter before they realize that there is a new chapter.
Independent of the fact that I believe the desired outcome (less free discussion) is itself a wrong direction, it also encourages EY to be careless with authors notes in the future, due to believing he can "take them back". It also punishes people for honest mistakes.
Maybe 8 karma isn't a lot to you, but it's what I lost just for disagreeing, not even for violating the rule myself. I also think that rot13 is a bad choice, since it requires external programs - implementing a spoiler tag for comments the way there appears to be one in use in some article posts would reduce the burden both to discuss spoilers and to read those discussions. (this is more "compliance is more trouble than it's worth" than "enforcement is more trouble than it's worth", but it's a similar kind of problem.)
I think a likely result is that people either shy away from discussing it at all, or have it as an implicit assumption (to their unrot13ed posts) and are caught in a trap when someone who doesn't know asks what they're talking about. Or we end up with a lot of noise whenever someone who isn't aware of the rule runs into it.
never frakking mind