Dumbledore and Harry don't actually do anything very different from each other in that scene. They're both blaming themselves instead of McGonagall. What's different is in how they express that. Harry is very clear about who he is blaming, and why; he tells McGonagall exactly what she did wrong when she asks to be blamed, although he still does not in fact blame her. Dumbledore, on the other hand, offers only comfort; he doesn't even tell McGonagall that he's going to blame himself, although she can very well guess.
It's also worth noting that Harry chooses an interesting fault to explain to Professor McGonagall. He doesn't suggest that, like Quirrell, she should have checked on all the high-value targets before leaving the room. Instead, he told her to trust her students more. This is something that McGonagall could actually do; it's much better suited to her than the more complicated, strategic options Harry would suggest for himself or Quirrell. So, although it's definitely not explicitly said this way, it's pretty easy to read Harry as giving advice here, which Dumbledore notably fails to do.
Flash of insight: Professor McGonagall has (had?) the identity feature "I know better than students what is good for them."
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 90. The previous thread has passed 750 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.
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