Do any other characters have super armor? That's an interesting little... is it a glitch? They obviously didn't mean for that to happen.
edit: Nono... At least for Aether he would NEED super armor, because if he were interrupted while in sword-throwing motion that would pose a problem. You can't have him throw the sword and then get knocked away while it's still in mid-air. I see that. But I don't see why Eruption can't be cancelled by an attack.