IFF is included in the cookie cutter spec now. If you don't have it, you had better be PvP. Beyond being an amazing boost in places where you don't have good raid composition (10mans or pugs), you also do not have to apply FF if there is anyone else in the raid applying it. Furthermore, taking it gives you a 6% stat increase (3%hit, 3% crit) which is pretty pro for 3 talents. Lastly with FF and MF up on the target, you're effectively giving SF a 6% crit boost from 7 talent points (IIS and IFF) which is all in all very good considering you will take IIS no matter what. For the good of boomkin everywhere, please take IFF