Blizz has the mechanical capacity to do so, simply looking at Frost DK shows it is doable. Now that Season of Discovery added this, I would not be surprised if they added such option in the War Within. After all, it was added to SoD as a fan favourite option, it would be both a shame and a wasted opportunity not to include it in retail.
This could actually be a decent way to further differentiate Storm build from Elementalist one:
- Storm build could focus on dual-wielding lightning strikes (pun intended) with Windfury on one of the weapons
- Elementalist build could use a two-hander, forgoing Windfury’s swing speed but gaining larger hits