Alright, you asked for it bud.
Clemency interrupts GCDs, only useful when a Healer is dead, otherwise provides nothing to the table. Healers can use O-GCDs stronger than Clemency without a GCD cost.
Most mechanics in raids punishes you for trying it, SE made sure you couldn't for most. Eden Savage, Pandae Savage Cover could do nothing than your own uptime benefit, any other mechanic straight out killed you. HG won't block debuffs than Damage down debuffs. And SE placed in mechanics for tanks as DPS obtains mechanics making it virtually impossible.
You can't clear Savage/Ultimate content 1st weeks without solid DPS, it's impossible. SE designed them around making sure every job is able to clear with their DPS outputs. Ninja was horribly useless for 2-3 weeks in Edens Gate Savage. Pld was near useless in Pandae Savage 1st week. Dungeons are meant to be cleared by everyone in the community, it's how they're designed. Speed is always going to be 1st choice if offered, majority do not wish 30-40 min dungeons.
That's how it's always worked, and works in Dungeons. Here I'll make a brain dead example. DPS Healer vs Pure healer: Wall pull with DPS Healer, pack dies in roughly 30-50s, loads of MP to spare and cooldowns to spare. Wall pull with Pure healer, you waste almost 2 minutes fighting the same mobs and individually run out of resources for the next wall pull. Hello? DPS saves resources, it saves time, it saves cooldowns, it stops mistakes. Sage cannot operate without DPS, Whm loses all it's MP without Holy stuns and fast kills, Ast/Sch are mechanically designed to DPS. Healing received 20-30% cut making DPS all the more worth it.
If I don't understand what you're talking about, you need to make better sense than trying to gate keep.