I'm sure you can, but you are making assumptions about people that everyone is capable of high speed, low effort writing for note taking.
just so we're clear, I'm not arguing you or your point. just that this system seems to work for this girl and it sure as hell would be easy (for anyone) to follow after the fact.
little side story: I'm dyslexic and have ADHD. It took me years to get a system down that worked for me for note taking. being both fast and a way for me to easily work through it. for me, in class it was fast and dirty, but I used one of those pens with multiple colors to write certain types of things in certain colors (definitions-green, general notes-black, important text within notes-red, side thoughts etc- blue). Then I'd go home and re-write everything like a book with uniform colors and rulers etc.