So, will it be viable to stance dance for Whirlwind?
If you stay in Battle Stance and refresh rend every 21 sec, Mortal Strike every 5 and Overpower every 6 sec, and hopefully you get one execute very 10 sec.
Then the graph would look something like this.
As you see the room between each Overpower and Rend is quite smal, so might not be worth it, also keep in mind that we still lose all but 25 rage when we change stance so you might not have rage for both Execute, Whirlwind and MS while your there.