Double magic may be a reference to Grossman's The Magicians. Warning: While there are many good things in the book, the viewpoint character is depressed and (in my experience) depressing.

I don't know whether Grossman has read HP:MOR, but he heads it off at the beginning of the book. Everyone at the magic school is a good bit smarter than average, but there's no one who's qualitatively smarter than that, and it's stated that enough unproductive research has been done into the roots of magic that it's generally considered to be a dead end.