Q: Full parties that feature a scholar and astrologian don’t have a MND party bonus... Do you have plans to change the party bonus for scholar or astrologian?

A: It’s not difficult to change this; however, by changing this, we worry that some may think of this as a nerf. Our view on this is that we should make the party bonus effective no matter what kind of healer combination is used, but we would like to hear from the players to see if it would be alright to remove PIE bonus, so please let us know on the forums. We would like to consider changing this.
Yeah, no. I don't know about anyone else, but as a BLM, I rely on the PIE bonus to go through a full opening rotation and have enough mana to use Bliz 3 > Bliz 4. Without the PIE bonus, I have to use Trans/Mana pot > slow bliz3 > Bliz 4.

Either keep it or give piety in each item like what's done for Healers. That'll take care of our MP needs and you can put the bonus on MND for all healing classes. Win/Win.