I haven't tested it. Mainly because I can't afford 3 good weapons (2 1-handers and a 2-hander).
I dual-wield 2 short swords. I've decided to do that because they both give me +5% crit. Finishers seem to do the bulk of the damage for me. Having +10% crit seems very valuable. More valuable than some extra dps from a 2 hander. I understand that slow weapons will make specials hit harder. But as finishers are triggered by crits, I think crit is more important overall.
Just a gut feeling.
Without addons to track dps, hits, crits, white versus yellow damage, etc, it is gonna be hard to find the real answer. I'd be interested in hard facts.
Oh, and of course an important fact is that I played a rogue in WoW, who dual wielded swords. Dual wielding, and managing my endurance as a warrior is almost the same as playing the rogue in WoW.
