I've recently started playing my priest and have been healing instances and the like. I've noticed that all the raid specs I have seen take 3/3 Holy Concentration but I'm not sure I see the value.
Everything I have read has said that the FSR doesn't really apply anymore with the changes to how spirit works, and with replenishment being based off intellect i'm not sure I see the benefit. I would say something like Surge of Light is much more useful.
Is this really a 'must have' talent?