
Originally Posted by
Ryaduera
For PLD if you consider you can HS once every 21s roughly, we're going to call it once every 25s since, like I said, it's only "roughly" every 21s and we want consistency here. 120/25 is 4.8 casts of HS, which is split between 4 seconds of 27.75% damage reduction (Remember, since it's 2 buffs it has diminishing returns on itself) and 4 more seconds of 15%. That's 4x4 each, so 16 and 16. Bulwark lasts 10 seconds and while it isn't a flat damage reduction, it's essentially 20% reduction for 10s on a 90s cooldown, so you can use it twice in a 2 minute window. So to sum it up: ((16*27.75)+(16*15)+(20*20))/120=9.03% Reduction (Redacted for an edit, see below)
GNB is basically the same math but instead we change the 20% reduction on Bulwark for 10% reduction on Camouflage (Ignoring Parry rate as we ignore PLD Passive block): ((16*27.75)+(16*15)+(20*10))/120=7.336% Reduction
DRK we will start with full charges of Oblation, meaning we can get 3 off in a 2 minute window, but outside of that that's the only thing we have for personal and unique mits. Then we do the math again for magic damage, knowing full well magic damage is so rare and you almost never would use Dark Mind off cooldown to any effect. First, physical damage. Since it's just 3 Oblation charges at 30 seconds of 10% reduction, this is easy: (10*30)/120=2.5% reduction.
Include Dark Mind, you can get 2 off since it has a 60 second cooldown. Still easy math here: ((10*30)+(20*20))/120=5.833%
Honestly this surprised me. I thought DRK would pull through in magic damage reduction with Dark Mind in a 2 minute window, but it looks like being the "Magic Damage Tank" isn't even actually happening when the math is said and done. Keep in mind, the actual disparity should be even larger after considering PLD Block and the Camouflage parry rate, but I don't really want to add the math for those steps. As I said, though, it would only increase that gap. In longer durations, DRK should catch up in magic damage reduction eventually because Dark Mind cooldown is 30s less than Bulwark and Camouflage, but honestly 2 minutes is already far too long to be holding a pull. I think technically DRK pulls a bigger average in a 1 minute window for magic damage as well, but I'm unsure because longer durations will start to show the weakness of Oblations longer cooldown. In pulls you are taking mixed damage at best so you're probably somewhere between the 2 averages, anyway, so I'm not convinced that the Dark Mind cooldown can even help it catch up. In fact, I'm quite convinced it can't when you consider the far superior cooldown of the even better cooldowns the other tanks get at level 82.
For clarity's sake, this math is basically saying that if over the course of 2 minutes 1,000,000 damage is applied to the tanks (Just using an easy to quantify number) in equal amounts of damage over each second (8,333 damage per second) the PLD reduces it by 90,300, GNB reduces it by 73,360 damage, and DRK reduces it by 25,000, or 58,333 if it's magical. This is without standard tank mits like the standard 40%, 20%, 10%, and 20% slow from Arm's Length that is basically 20% reduction as well, as those are standards and this math is intended to show the difference between tanks unique cooldowns.
So yeah pretty sure Oblation just isn't enough and TBN isn't as efficient as it looks at a glance when you consider the total HP Shielded is about equal to the total HP a PLD can restore within the same 2 minute window. In a scenario with constant incoming damage, healing is harder to calculate actual efficiency since overhealing is health not used that shielding doesn't suffer from, but at this difference does that even matter? I also calculated the healing without crits because that complicates the math a lot. I think we have 15% crit rates now without melds and about 150% crit potency and I'm not about to do that part of the math.
These numbers show that DRK isn't even succeeding at the thing it was meant to succeed at. Oblation just isn't enough.
EDIT: Just did Expert as PLD and realized blocking is not 20% reduction, it's 16%, so to adjust the number, ((16×27.75)+(16×15)+(16×20))/120 =8.36% or reducing 83,666 from 1,000,000 damage over 2 minutes.