You guys are not clearly understanding how the player handles copies of tunes in multiple playlists.

When you select "Replace Tune", it replaces that instance of that FID file on the hard disk. It doesn't go searching for stuff which happens to have the same title, it only replaces that particular song file. Besides, you wouldn't want it to replace every song with the same title. If it did that, I'd lose four of my five different versions of "Closer to the Heart".

The player doesn't care if the song from a movie soundtrack is the same as the song from the greatest hits collection is the same song as the song from the original studio album. You deliberately uploaded the song three different times, so there are three different copies of the song and the player thinks they are all completely different. (And, technically, they ARE different because they were mastered differently on each of those CDs.)

The only time that "Replace Tune" will replace multiple playlist-instances of a song is if they really are the same song, copied between playlists, as described here.