Probably just pattern matching on it, and Quirrell is ridiculously powerful, but he was the one to notice and stun 100+ females summoning Harry to the ground.
And note Quirrell's comment:
“I should have foreseen it myself,” Professor Quirrell said,
He thinks he should have anticipated the actions of young girls taking actions based in romance. That's about the last context a grown man expects to be able to anticipate events.
Pattern matching as well, but the pattern matches quite a lot.
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.)
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