Imagine this conversation: A new student appears at my door and says hi , I remark to her about how familiar she looks, after a few minutes of detective work we abandon any attempts to figure out if we know each other. She volunteers her full name and now I know for sure we have met before but still no luck figuring out where. Anyway, I write a few random musical scribblings on the pad and she looks at me and says “Did you used to teach me when i was 12?” It turns out that my handwriting is so bad, she remembers it from 15 years ago.