Echoes

The Echoes are significant because they happen when R & G are not needed and therefore don't really seem to matter to the other characters. When R& G are noticed is when they are needed and have been sent for because that's all they are good for. It's when they are talking amongst themselves and no one cares that the echoes take place as if telling the world that they still are there. It seems that everyone forgets them and then they echo and then everyone else is reminded that they do exist and therefore can use them.