What to manage as a tank?

[CKNovel]

Nope.. there is something called enrage in savage

If healer die all party die they have a clear thing to manage

But tanks I don't see any thing to manage

Go ahead, play savage without managing your mitigation or DPS and we'll see the result.
DPS from everyone is very important in savage/ultimate, if you experimented it, you would be aware of it.
Tank DPS is roughly 70~80% of a melee DPS, it's extremely valuable. If you can clear with a tank that doesn't DPS it means your group is already overgeared.

You should also be aware that in savage, damage taken from busters and raid wide are above player HP, there's many of them you absolutely can't survive without tank mitigation.

Be sure that if tank had "nothing to manage" you would see 1 tank and 5 DPS or 6 DPS in savage content.