Hey, I do what I have to when people double/triple team me or almost take one of my team's zones. Besides, it's a very risky move. If you miss either of them, you just wasted a grenade AND melee charge. To be completely honest, the combo is pretty much as deadly as the Stormcaller's grenade by itself. So I don't really see it as "OP" as much as a use of resources.