Would this not make sense? I guess sword oath is more for DPS/OT stuff, so you wouldn't really need a shield.
It'd be kind of cool if, when you were in sword oath, your shield didn't show and your sword was sheathed on your back.
Wouldn't that be sick? Or... just add some kind of Emperor's New Shield or something like that
I guess I'm just a fan of greatswords and sad my paladin can't use em... but hey, cool idea though, right?