PLD Question. Does this materia setup work?

[Warkupo]

Paladin curing is not a completely absurd idea, and CAN save a bad group that's gone south. You're better off doing it with a mix of Crit and Skill Speed, however; Even if you're spamming clemency you're still spending most of your time with melee combos so skill speed is more relevant for refueling your mana supplies so you can keep Clemency spam going. Crit-Clemency is such a big heal that you can often "skip" the next clemency GCD in favor of another MP restoring melee combo.

Before Atonement was a thing I'd do a pseudo "combo" where I basically just spammed Riot Blade without finishing with Royal Authority or Goring Blade. This was mostly for sudden emergency situations where the healer either died or disconnected, or sometimes if the group just wasn't very good or familiar with the mechanics, ooor if I was just soloing things you really aren't supposed to be soloing and I just needed to out-endure the enemy. These days Atonement lets us keep our mana supplies fresh without completely neutering DPS, but it is worth noting that back to back Riot Blades do still technically regenerate more mana per GCD.

It's not a bad idea as a PLD (or any caster) to keep an emergency supply of Ether. While we're all pro-paladin on this forum and would never cast clemency, it's nice to be able to get your mana back if you DO have to save some hapless Dragoon swimming in AOE so you don't have to delay Requiescat or resort to cheesy Riot-Blade combos. I like to also keep Antidotes and Silence-Curing potions on me too because I don't fully trust my healers not to just ignore me when I get these debuffs.

I definitely do think the guy you were with was either trolling or just... trying something different at your expense. Everything I just outlined above is more of an emergency situation tactic you can do to MAYBE pull dumpster party out of a fire, and not a tactic I would generally expect anyone to be trying on purpose.