Well, sure, that's exponential growth for you. I'd actually rule out the scenario I present in the grandparent on narrative grounds: it's not interesting from a plot or a rationalist perspective to be interrupted every chapter or two with a description of Harry's latest trade, or even with his latest plan to wring another 5% out of his capital. (Maybe not that latter -- Spice and Wolf pulled it off. But that's a different kind of story.) Point is, this doesn't need to be attention-getting in or out of story, just repeatable. There are boring options that would work (day trading with a Time-Turner being only the first to come to mind). Since that's an unstable state for a story and the debt could easily have been omitted, at this point I'm waiting for the other shoe to drop.
I'm not expecting that shoe to come in the form of unexpected changes to the financial structure that the early chapters set up, though. That does paint the Wizengamot in a rather unflattering light, but these are people that have only the vaguest idea of what cars are -- an enormous blind spot concerning the Muggle world is quite consistent with the established culture.
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 81, which should be published later today. The previous thread passed 400 comments as of the time of this writing, so it will pass 500 comments soon after the next chapter is posted, if not before. I suggest refraining from commenting here until chapter 81 is posted; comment in the 12th thread until you read chapter 81. After chapter 81 is posted, I suggest all discussion of previous guesses be kept here, with links to comments in the previous thread.
There is now a site dedicated to the story at hpmor.com, which is now the place to go to find the authors notes and all sorts of other goodies. AdeleneDawner has kept an archive of Author’s Notes. (This goes up to the notes for chapter 76, and is now not updating. The authors notes from chapter 77 onwards are on hpmor.com.) When posted, chapter 81 should appear here.
The first 5 discussion threads are on the main page under the harry_potter tag. Threads 6 and on (including this one) are in the discussion section using its separate tag system. Also: one, two, three, four, five, six, seven, eight,nine, ten, eleven, twelve.
As a reminder, it’s often useful to start your comment by indicating which chapter you are commenting on.
Spoiler Warning: this thread is full of spoilers. With few exceptions, spoilers for MOR and canon are fair game to post, without warning or rot13. More specifically: