A fun take-off on musicology:
There's a serious moral to this, of course, that one needs to be careful about how much certainty to pretend about conclusions reached regarding ancient history. I like to ask students how much they think a future musicologist could conclude about jazz music lacking recordings, but only with written-out arrangements, how-to books, and lead sheets.
All we know about Baroque music is written-out arrangements, how-to books (treatises), and lead sheets (figured bass). Surely when you booked a band for your Baroque party they spent the time improvising on ground basses, but how little we know about what that must have sounded like. And how-to books assume some kind of prior experience listening to the music. That's one of many reasons I'm skeptical of the authentic-performance movement; some of their conclusions might be as ridiculous as the Beatles history shown above.