I'm going to take a shot at this because SCH's kit definitely caters to the current raid design that S-E has built. Even if it's unintentional catering, it's still catered too.
Raid design builds around set timelines and mechanics that need to be dealt with. Assuming everyone dodges mechanics correctly, this also means there is an exact amount of damage that needs to be healed for. That's why we have these fancy little time lines that we can build our cooldowns around.
SCH's kit is perfectly suitable for this style of healing. SCH is a cooldown based healer - Lustrate, Indom, Excog, Sacred Soil, Whispering Dawn, Fey Covenant, and Fey Union can all be used to repair or blunt damage on both single target and raid-wide busters without spending a GCD. Deployment Tactics can blunt more damage within a single GCD. When you can plan out ALL these tools, it leads to SCH spending a lot of heals with minimal GCD costs, and thus minimal loss of GCDs for DPS spells.
Let's take the O11S fight timeline I posted earlier and just focus on the raid busters:
SCH can
- [00:07] Indom the Atomic Ray
- [00:26] Fey Covenant and Whispering Dawn the Flamethrower
- [03:02] Indom the Delta Attack
- [03:36] Adlo and Deployment Tactics the Flamethower (GCD)
- [03:43] Indom the Ballistic Impact
- [04:16] Indom the Atomic Ray
- [04:30] Succor the Peripheral Synthesis (GCD)
- [04:48] Indom the Electric Slide
- [04:59] Whispering Dawn the Peripheral Synthesis
- [05:48] Sacred Soil, Fey Covenant, and Indom the Flamethrower
- [06:28] Whispering Dawn the Ballistics Damage
- [06:40] Adlo and Deployment Tactics the double Wave Cannon Kyrios (GCD)
- [06:50] Indom the Long Needle Kyrios
- [07:10] Succor the Atomic Ray (GCD)
- [07:58] Indom the Atomic Ray
- [08:07] Succor, Fey Covenant, and Whispering Dawn the Flamethrower
- [08:59] Indom the Engage Ballistics System
- [09:11] Adlo and Deployment Tactics the Double Wave Cannon Kyrios (GCD)
- [09:22] Whispering Dawn the Long Needle Kyrios
- [10:04] Indom the Charybdis
- [10:29] Whispering Dawn, Fey Covenant, Sacred Soil, Indom all the Atomic Rays
This probably isn't optimized either, nor have I accounted for all the variables. So, 21 AoE attacks and SCH only has to basically spend five GCDs to have some solution to all of that. Add in two or three Succors in between to help out, though your co-healer should be taking some of the healing off you as well.
In an ideal world, SCHs myriad of options means they should be the primary healer in the engagement, with the other healers providing back up with their own planned CD usages (Earthly Star, Asylum, Assize) or when necessary with GCD options because SCH's higher end GCD spells are significantly more MP-expensive than AST or WHM.
With SCHs taking the vast majority of the healing responsibilities, this opens up many more healer GCDs to use and thus be an overall rDPS increase to the party. This doesn't include the consistent damage SCH adds to the raid via Chain Strategem and of course the free GCD-free regen they have going for 3,696 potency/minute on the MT when you account for Rouse; let alone the 2,851 potency Fey Union gives when fully charged and consumed.
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What sucks with the situation is that buffing WHM or AST to SCHs level doesn't really help for two reasons:
- All healers are viable to clear the content. If we increase the power level of the healers, it just trivializes the content even further, from a healing perspective.
- All buffing a healer beyond each other is change the meta composition without changing the competitiveness of each healer. The kits are too similar to the point where the inferior healer will be deemed unsuitable because there are very few things in each healer kit that stands out.
I expect a shift in 5.0 because new expansion brings new tools. I don't quite know how they're gonna balance SCH though. I'm of opinion the SCH kit will always be meta because of how well crafted it is and how well it works with content design. The only time this isn't the case is when SCH is nerfed so hard it's skill ceiling is far too hard to attain without a ton of effort.
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TLDR: And combination of SCH's single target healing kit, raid healing kit, DPS buffing kit, and how well the SCH's kit design compliments the current raid designs allows SCH to shine as a healer at a much higher peak versus the other two healers.