In addition to all of these edge cases, it doesn’t help that the metadata services have a lot of inconsistency as well. Say I have a song X that was performed live on DATE at some VENUE. It may show up as titled “X”, “X [live]”, “X (Live DATE)”, “X (DATE VENUE)”, and so on. Stuff that should be in metadata ends up in strings embedded in song and album titles, which makes for a big mess. I curate a huge collection and trying to keep my metadata consistent is a massive headache. I think I’ve tried just about every tool out there and still haven’t found one that I’m happy with.