- This thread has run its course. You will find newer threads in the discussion section.
Another discussion thread - the fourth - has reached the (arbitrary?) 500 comments threshold, so it's time for a new thread for Eliezer Yudkowsky's widely-praised Harry Potter fanfic.
Most of the paratext and fan-made resources are listed on Mr. LessWrong's author page. There is also AdeleneDawner's collection of most of the previously-published Author's Notes.
Older threads: one, two, three, four. By tag.
Newer threads are in the Discussion section, starting from Part 6.
Spoiler policy as suggested by Unnamed and approved by Eliezer, me, and at least three other upmodders:
You do not need to rot13 anything about HP:MoR or the original Harry Potter series unless you are posting insider information from Eliezer Yudkowsky which is not supposed to be publicly available (which includes public statements by Eliezer that have been retracted).
If there is evidence for X in MOR and/or canon then it's fine to post about X without rot13, even if you also have heard privately from Eliezer that X is true. But you should not post that "Eliezer said X is true" unless you use rot13.
It would also be quite sensible and welcome to continue the practice of declaring at the top of your post which chapters you are about to discuss, especially for newly-published ones, so that people who haven't yet seen them can stop reading in time.
Ch. 57-58: I'm finally forced to abandon my original misplaced expectations about the fic. I thought it was trying to be realistic in the Watt-Evans sense, but now I see that awesomeness is more important to Eliezer than plausibility. (Scaring away twelve Dementors who approach close while the Patronus is down? Building a rocket from memory?) Okay, this kind of fiction makes for an enjoyable read too.
Now that I think of it, the plan has been doomed since Ch. 56, and possibly earlier. Harry's idea of dealing with McGonagall involves using the Time-Turner again. This means a version of Harry must leave Mary's Place before Harry and Quirrell begin their elaborate precautions, and maybe before they even order their food (Ch. 51). Whoops.
As long as an object exists you can transfigure something to it. You don't need to know everything about a device to transfigure a duplicate.