When Harry lists all the ways he could have prevented Hermione's death to McG, he is quite upset and mentions that he could have asked for everyone to get communication mirrors. This is overheard by Dumbledore, as we learn later in the chapter. However, as far as we know, Harry has seen communication mirrors only once: when he was in Azkaban. Dumbledore should be able to deduce this and thus that Harry was indeed involved in the break out.
Given that Harry talks with the Defense Professor about how the magicial world works and reads a lot of books I find it unlikely that Dumbledore would think that Harry doesn't know about the mirrors.
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 98. The previous thread is at nearly 500 comments.
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.)
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: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26.
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: