I'm lazy, I don't want to join my wavs or mp3s. The Golden Slumbers medley was multiple tracks on the CD, that's how I store it. But when I hear the first part randomly, I want to hear the rest. Likewise, I don't want to hear it start in the middle. But, these should be 2 separate attributes (can stand alone, has linked children) because for instance, "Stay" by Jackson Browne is reasonable without "The Loadout" but "The Loadout" sounds silly without "Stay" right after it.