Playlist and database is different. When you see a singles page, that is the database. It is stored on the blockchain. Nothing in there is duplicate. When youhave a playlist, that can be anything...in the database or not.
So if you submit a Johnny Drille song and it is in there, it will not be added. If you start a Johnny Drille playlist and embed 12 or 15 YT songs in your playlist, the playlist will be added to the appropriate pages.
Okay, well understood. Thanks so much for the detailed explanation.