When the patch went out for the windfury "hidden" 3 sec cooldown I just had my main-hand use windfury (Reflex blades with 2.70 speed) and my off hand with frostnova (Stormweaver warblades with 1.60 speed) the reason is want to slow down my enemy because gives me a higher chance to unload my windfury on them (you only have a 20% chance). So I ask you would you rather slow down you enemy so you have a better chance of hitting that 20%? if you think duel wielding 2 slow weapons is the way to go then you might as well carry a big slow two-handed weapon and forget putting talent points in duel wield.

Remember this combo: Stormstrike, one of your shock spells, turn his face into jelly and then another shock spell. Rinse and repeat