At this point in the story Harry has never even heard of Avada Kedavra, never mind what someone who's been AKed would look like.
[EDITED to add: The relevant question isn't whether there are in the Potterverse or the Methodsverse ways in which wizards might be able to know what happened that night despite there being no survivors other than the infant Harry, but what rational!Harry could reasonably have thought possible and plausible.]
..."The Dark Lord came to Godric's Hollow," said McGonagall in a whisper. "You should have been hidden, but you were betrayed. The Dark Lord killed James, and he killed Lily, and he came in the end to you, to your crib. He cast the Killing Curse at you. And that was where it ended. The Killing Curse is formed of pure hate, and strikes directly at the soul, severing it from the body. It cannot be blocked. The only defense is not to be there. But you survived. You are the only person ever to survive. The Killing Curse reflected and rebounded and
Update: Discussion has moved on to a new thread.
The load more comments links are getting annoying (at least if you're not logged in), so it's time for a new Harry Potter and the Methods of Rationality discussion thread. We're also approaching the traditional 500-comment mark, but I think that hidden comments provide more appropriate joints to carve these threads at. So as of chapter 67, this is the place to share your thoughts about Eliezer Yudkowsky's Harry Potter fanfic.
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. The fanfiction.net author page is the central author-controlled HPMOR clearinghouse with links to the RSS feed, pdf version, TV Tropes pages, fan art, and more, and AdeleneDawner has kept an archive of Author's Notes.
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: