I stand corrected, though here's a better resource on its slow phasing out. Unrelated, I miss stormblood BLM. Truly the best iteration. Loved the crap out of mana shift.
No, mind was the old +healing stat. Piety was +mp.
The reason why I was wondering if BLMs could boost piety with leveling is because I had the impression piety wasn't a primary stat, since I remember needing to meld piety as a BLM in HW. IIRC the stats you could spend your 30/35 points on were STR/DEX/INT/MND/VIT, but I need to find a source on it again.
Ye Olde Cleric Stance really showcases this, since it swapped the primary heal stat with the primary magic DPS stat.