Just dont ever use it. I started out with it when kiting adds on Garrosh HC, but found that with just the right ammount of practice on the boss, it wasnt needed at all. I ended up with Xuen to do more dmg, and help with the breakpoints we had to reach. Kiting those adds can be done with just normal roll, and with Tiger's Lust.
My advice is: Forget about that spell, and roll with Xuen for (nearly) all fights. The vengeance dmg gains of it is insane.