It's sort of useful. You can stack it with SCH/AST shield and mitigate 4k+ damage from a tank buster so you don't have to panic and heal back that amount. But it's super mana-intensive to use it frequently so I generally don't use it.

It's weak enough that you could never cross-class it on SCH/AST and would never notice a difference.

As the person above me said, it's probably better to make the PLD cast it since they don't really need the MP anyways.