I saw a character screen shot where he was doing just that. Anyone know how that works???

Twin swords are nothing more than a shield that looks like a sword. You can download this mod to make it look like your fighting with 2 swords http://www.tesnexus.com/downloads/file.php?id=16679.
Edit: Oh btw I'm pretty sure sephs animation does NOT work with deadly reflexes.

It is called Seph's dual wielding, but it is merely animation, you cant wield your extra weapon in your inventory... Look it up it should have an OMOD version too...