I imagine that Harry can tell her the truth in a few years, after they've saved the world, and she's learnt more, and there's just more distance from the event. But I don't know if she'll be fooled that long, or conversely if Harry will ever be willing to tell her. I'm more inclined to think that the Vow might prevent him from telling her, if he's worried that she won't be able to offer him good advice afterwards.
Hm... I'm going to go out on a bit of a limb here and predict that Harry will tell her quickly OR will want her to learn Occumency and expect to tell her quickly after she has. Confidence 70%.
edit: yay
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 116.
There is 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.)