Bring Cleric stance back

[RecoveryPotion]

I understand they removed it for balancing purposes, but I think it would be cool if healers can get the cleric stance back. However, for said balancing purposes. It would work similarly to BLU basic instinct where it only boosts the damage outside instances & Parties.
Same for tank stance. It can boost the tanks' damage outside instances & parties but once they join one the damage increase will be gone.

I wasn't around when this was implemented , what did cleric stance do?