Have fun with it! This seems like a great example to encourage further analysis because you still don't have a testable quantitative hypothesis for why it was h

Have fun with it! This seems like a great example to encourage further analysis because you still don't have a testable quantitative hypothesis for why it was harder to read. Makes me want to start coming up with metrics, too! Of course there's a big list of readability metrics, but it's way more fun to discover them on (y)our own. That said, I too was a little surprised when you had a heading titled "The classic graphs" without actually having perspective in the field for what would be classic.