The Definitive Dark Knight Guide

[Jpec07]

Wow, a thread that got necroposty'd twice.

Mercy Stroke is incredibly weak. It's only 200 potency, has a 90s recast, and can only be used when the enemy is below 20% HP.

Foresight is stronger, providing a good bit of reliable physical mitigation, which can be invaluable for tankbusters. I usually pair it with DA-DD when tanking trash or during a white-damage phase, which usually does a pretty good job of mitigating incoming damage.

Bloodbath is also stronger than Mercy Stroke because you can use it for the whole fight, with a very similar cooldown. It also provides more healing over time than Mercy Stroke, because the potency healed over 15s is 25% of what you put out (on a single target, that can mean 256-627 potency healed, depending on procs and oGCD cooldowns, while the number balloons as you get into multi-target situations). When compared to the possible 200 potency self-heal from Mercy Stroke, there is no question which one you should take.

EDIT:

Surviving when playing as a tank class is the absolute bare minimum of what you're expected to do. You don't get a gold star for mitigating attacks with the correct amount of defensive cooldowns. Nobody will give you a standing ovation for understanding snap enmity generation. These are basic pass-fail checks for a tank. What separates a "good" performance from a mere "pass" is your ability to position smartly, and to maximise your dps while still competently performing the fundamental requirements of your role.

Ah yes, the old, "good tanks focus on DPS" argument. While it is true that every Tank needs to be able to focus on their damage, being able to do that is secondary to winning an encounter (AS1-4 was unique). The best tanks are the ones who can adapt to any situation that's thrown at them, and who are best able to recognize and deal with mechanics as they encounter them. Progression raiding is about learning the fights and their mechanics more than anything else, and learning what cooldowns to use where to empower yourself to focus on other things.

When you're learning a fight? Focus first on mechanics and positioning, then on mitigation, and once you've got that down, THEN you can begin to figure out where you can push more DPS. A tank's main focus is holding hate and surviving--anything else is incidental.