but why is it unlikely for him to have not known, and also not been responsible for killing her?
The point is not what he knew then, but what he knows now. If he didn't kill Hermione, someone else did. Whatever would motivate someone to kill Hermione is very likely to motivate them to frame her and get her sent to Azkaban, and require the same ability to evade the Hogwarts wards. So if Lucius did not kill Hermione, this is strong evidence that she was framed. Contrapositively, if Lucius still denies that Hermione was framed, that is a tacit admission that he probably killed her.
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 97. 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.
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: