another feature/side effect is that you can use any instrument to play any part of a written piece, as long as it's physically possible to play the notes as written. and if not - you can improvise easily by dropping superfluous or unnecessary components/notes without changing the overall sound of the music.
Another side effect is that as a guitar player you can look at the tuba player's part to figure out what he is playing even if you have no idea how to play tuba, if you read music. With tablature only a guitar player will know what you are playing.
