It is really very clear that they aren't actually responding to player raised issues. The team thinks the class is fine and that is all that matters.
Direct question about dark passenger: No comment
Forums: Less utility, dps, and lower up times on mitigation than Paladin and Warrior. No Comment.
Ok.
Let's look at what tanks got in this expansion:
Paladin Gained:
1. Gets to block magic, can refill its gauge quickly getting a self shield that works really well on tank busters and mitigates only 4% less than Dark Knights strongest skill.
2. Gained the ability to have uninterruptible casting, as well as had all of its mana costs cut in half.
3. Cover buffed to mitigate damage and cover magical damage
4. Party shield
5. New powerful magic attack.
6. oGCD skill which buffs its hard hitting magical attacks/increases its self healing if you choose to. Buffed by its physical cooldown
7. Several potency buffs to its dps combo.
8. The ability to share your mitigation with your cotank
Lost:
1. Made several contributions to the new CR system, has room to slot everything back.
2. Halone combo debuff removed
3. Foresight
4. Bloodbath
Warrior Gained:
1. Gained an oGCD gap closer on half the cooldown and 33% longer range than the dark knight equivalent. Used in dps rotation as a guage dump, generates enmity.
2. Gained a resource cut allowing it to double the number of its hardest hitting moves, accessible every other burst window, prevents many negative effects which could work against it (push backs, stuns, and binds, and sleep).
3. Gained a powerful oGCD attack which ignores its tank stance penalty and is buffed by its tank stance, a defensive cooldown, and its offensive cooldown.
4. Gained a party wide shield on a short cooldown
5. Potency buffs and guage buffs to its dps combo
6. Selfsustain buffs to moves in tank stance
7. Removed the requirement of needing to burn its mitigation in order to fuel burst phase.
8. Gained access to Rampart, a better alternative to its native cooldown
Lost:
1. oGCD Stun
2. Raid wide mitigation
3. Low potency Dot removed
4. Lost foresight, but gained rampart
5. RIP Bloodbath
6. Mercy Stroke
7. Lost access to second wind through CR system
8. Internal release (crit version)
Dark Knight Gained:
1. Gained Delirium buffing resource generating abilities, is 1/4 the potency of the warrior and paladin equivalents.
2. Gained an AOE move which helps restore mana
3. Gained a single target hard hitting move.
4. Gained a shield which can be used frequently but can be risky to use as frequently as is available.
5. Resource generating abilities buffed to generate the new resource.
6. Potency of dps combo raised, blood generation added to dps combo ender
Lost:
1. oGCD stun, the potency of the stun, and the proc mechanic reseting the stun
2. Lost a fluff cooldown in dark dance
3. Lost Reprisal, 250 potency with a damage down debuff
4. Lost access to foresight as a cooldown through CR system
5. Dark Passenger potency cuts to oblivion
6. Unleash potency cuts
7. Contributions to the CR system cannot all be slotted back without giving up necessary tank moves.
8. Selfsustained lowered
9. Lost a high potency dot
10. Lost access to Mercy Stroke through CR system
11. Magical debuff from DPS combo removed (RIP 3.x Delirium)