http://www.youtube.com/watch?v=Fe6tos8EVoQ I'm not going to pretend to understand the logic of pitting two character's swords against each other and only their swords, but someone else did. Zero is the character I played the most in Borderlands 2, but his sword isn't a weapon that you can constantly use. It's a special feature so it seems weird that a non-playable sword would be pitted against a non-playable characters sword...
Via Fashionably Geek