If it's worth saying, but not worth its own post, even in Discussion, it goes here.
Just tons. For example, Harry's instructor, Mr. Bester, is a double reference.
EDIT: And obviously the Bester scenes contain other allusions: back to the gold-silver arbitrage, or Harry imaging himself a Lensman, come to mind.
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If it's worth saying, but not worth its own post, even in Discussion, it goes here.