New Job: Pugilist Tank

[Kitru]

If the healer has to pay more attention then before then um, why would you use that style of tank then?

Generally, the trade off would be slightly higher mean mitigation (you have to pay more attention but are rewarded in having to use fewer resources to keep them alive). When you're talking straight equivalences, like compared DR to the combination of hp and evasion, the math ignores stuff like spikiness because it's looking for the equivalence not the practical balance concern. As I see it, an evasion tank would probably get roughly 22.5-25% evasion along with 30% +hp, both of which exist to make up for the significantly spikier damage profile. Spikiness is a calculable attribute, but it's got be balanced using heuristics and intuition rather than straight math (the math gives you a guideline that has to be honed down to account for the abstract). It's done in the same way that Defiance is balanced: to be equal with Shield Oath, Defiance *should* have 25% +hp and 25% +healing, but it only has 20% because WAR brings in self healing which necessitates a reduction in their increased mean mitigation. The math behind it isn't absolutely solid, mainly because the value of self healing shifts greatly depending upon how much damage you're taking over a period of time, so it's tweaked to get to as close to balanced as possible.

[Maku]

Generally, ...

That just reads as standing around more waiting to heal because you can't look away to DPS or heal other people because you have to be ready at a moments notice.

[Kitru]

That just reads as standing around more waiting to heal because you can't look away to DPS or heal other people because you have to be ready at a moments notice.

Which is kind of the point. Spikiness is synonymous with predictability. If you can predict the amount of healing required less accurately with one tank than another, you're going to have to pay more attention to that less predictable tank. The "payout" for not being able to predict how much healing is going to be required over the short term is needing to heal less over the long term. It actually works out pretty well for balance purposes.

[Firepower]

But it doesn't imagine that this spike damage happens on a big hit (mountain buster is a good example) and the tank goes down in 1 hit. Just because of a bad RNG the party is wiped, if this happens more than once the party disbands and everyone says, get a normal tank that doesn't have the ability to insta-wipe a party for no fault of its own. So nobody then uses the evasion tank because people don't like to waste time wiping due to dumb luck. Or it goes the other way and it consistently evades big hits thus making WAR and PLD useless because what is the point in mitigation if the other tank avoids it all together.

[Kitru]

But it doesn't imagine that this spike damage happens on a big hit (mountain buster is a good example) and the tank goes down in 1 hit.

I'm gonna go over this again because apparently people keep missing it: an evasion tank would by necessity have +hp because, without it, they would have dramatically worse eHP compared to the other tanks, which means that it wouldn't be balanced. With 25% +hp, any attack that would 1 shot the theoretical evasion tank would 1 shot a PLD or WAR because they have the exact same eHP. The situation you describe would not happen.