Cure 3 aoe to small to use.
4 yalms (or whatever the measurement is) is smaller then most bosses. The only time this spell can be used efficiently is when you have all the melee dps stacked on each other. The mechanic of the spell I would think would be that it would replace a Cure 2 on the tank when the melee dps get hit by aoe. Figuring in the mechanics of the melee classes and how to maximize their damage by moving from the side to the rear, cure 3 is totally inadequate to even cast on a dps as they will move out of range of each other constantly. It doesn't need to be as big as medica, but it should be able to reach the dps from the tank.