Originally Posted by
Unlimited Power
I guess it may change things in raids that are often primarily single target, but for m+ I very much doubt the change to Stormkeeper will mean anything. It's still limited to 3 targets and Sundering is uncapped and has the added benefit of interrupting every target hit, including uninterruptable casts, and it's not even on the stun DR.
Furthermore, while the damage of Sundering is hardly as impressive as we've seen in previous expansions, the fact that it procs windfury on every target hit (which, again, is uncapped) makes it deal significantly more damage during Doom Winds.
Long story short, it's possible Stormkeeper will see use in raids, but I very much doubt it'll change anything in m+ or even pvp. That said, I haven't looked at any theory crafting or number crunching, so I guess I could be wrong.