WAR love is out of hand. Twelve forbid the other Tanks stand out in any way.

[Disc]

For the sake of it lets count pot for all tanks ( single target In dps stance)

Those numbers are useless like that. More to come.

Combos
Hard+Spin+Power = 670
Hard+Syphon+Delirium = 680
Hard+Syphon+souleater=660(820 w/ DA)

PLD Combos
Fast+Savage+Halone = 610
Fast+Savage+Royal Authority = 690
Fast+Riot+Goring = 600((920 actual)+600/minute from DoT)

WAR Combos
Butcher’s Block – 630
Storm’s Eye – 610
Storms’ Path – 590
Fracture – 100((300 actual) +400/minute from DoT)
Fell Cleave – 500(5 wrath)

DRK oGCD
Carve & Spit – 100/minute(450/minute w/ dark arts)
Scourge – 500(1000/minute)
Salted Earth – 525(700/minute)
Plunge – 200(400/minute)
Low Blow – 100(200+/minute)
Total oGCD: 2400/minute+- low blow
2760 w/ Darkside
3163 w/ Darkside + Dark Arts

PLD oGCD
Spirits Within – 600/minute
Circle of Scorn = 250/minute
Sword Oath – 50/auto(1442/minute)
Total oGCD: 900/minute(2342 counting bonus from autos)
2811 w/ 10% avg Fight or Flight

WAR oGCD
Brutal Swing – 150/minute
Total oGCD: 150/minute
180 w/ Maim

Roughly 24 GCD per minute

Dark Knight
This is iffy because it’s hard to say exactly how many times you’ll get to use Dark Arts
Dark Arts+Souleater Only: 6560 potency/minute(7544 w/ Darkside) Not practical
Delirium Combo Only: 5440 potency/minute(6256 w/ Darkside)
Half & Half: 6000 potency/minute(4 dark arts used, 6900 w/ Darkside) - Most similar to actual

Paladin
2 Goring + 6 Royal: 5980 potency/minute(6578 w/ FoF)
Note: Starting another Goring instead of Royal will result in higher overall potency, but not upfront

Warrior
3 Storm’s Eye + 4 Butcher’s + 2.4 Fell Cleave + 2 Fracture: 6150 potency/minute(7380 w/ Maim)
Wonky math, very rough overestimate

DRKTotal Potency Per Minute
8400 Base
10063 w/ 5 Dark Arts + Darkside

PLD Total Potency Per Minute
8322 Base
9389 w/ FoF

WAR Total Potency Per Minute
6150
7380 w/ Maim
If we consider Berserk a 50% damage bonus up for 22% of the time that comes to 8198 potency/minute. I have no idea how close that estimate is for Berserk.(Berserk estimate is very likely wrong)

Using these numbers and PLD as base tank potency...

Unbuffed
PLD 100%
DRK 100.9%
WAR 73.9%

With Buffs
PLD 100%
DRK 107%(aftermath- 109.8% if you count Bloodweapon)
WAR 87.3%(Berserk estimate is very likely wrong)

This does not include TP issues, breaks in fights, etc that will raise the value of Berserk & Fight or Flight. Just a pure 60 second potency estimate based on buff averages.

-edited for slip in WAR combo estimates & again because WAR math
-edit this does not count WAR crit rate either

Even with them all getting slashing debuff, there's still a gap between the 3.

And is it really fair to assume slashing debuff for all three? WAR is going to be in a composition with it available 100% of the time (WAR/WAR, WAR/PLD, WAR/DRK). PLD and DRK will only be in a group that has it available 33% of the time (PLD/WAR, PLD/DRK, PLD/PLD or DRK/WAR, DRK/PLD, DRK/DRK). And that also assumes both tanks are always on the same mob.

The difference between the damage output of a WAR/DRK or WAR/WAR composition and PLD/DRK composition could be anywhere between 30-50%.

That's not how parties work. You will bring a WAR if you are worried about damage taken or dealt. No ifs, ands, or buts.