But I definitely think using Defensive Stance to track whether someone is a “tank” is better than a percentage of damage taken. I also think it would be best to try to catch only the Main Tanks and not the “I tanked one add for a couple of seconds” as “tanks.”
in Lucifron I didn’t use def stance, and yet, the damage taken wasn’t that high, on previous kills I received more damage, and wasn’t flagged as tank.
In Garr I was only 5 secs (11% uptime) trying to minimize damage when I got aggro.
So, if I was marked as tank on Luci when I didn’t cast def stance and received much less damage from adds and boss than I got in Garr, I guess in both cases, I was flagged as tank because of the damage taken.
It’s not about damage taken currently. It’s about % of melee hits taken. Anyway, we’re discussing solutions/changes here and don’t really need more examples of where the current algorithm is getting it wrong. All those issues are known at this point. 
I can set the threshold per fight, so that might be a good way to think about it. Maybe for MC, Onyxia and BWL, say how many tanks there are, and what % of Def Stance makes a good threshold for that boss in particular.
I would say 40% is an acceptable threshold in general (that’s half of the fight outside of execute range and should also still correctly catch fights with 2 alternating tanks, when one of them goes for damage often). You don’t have to catch the warriors that just picked up an add for a few seconds. They are usually not geared as tanks and deal damage the remainder of the fight.
Also to look at the reverse: No damage dealer will be 40% of a fight in def stance unless he actually had aggro for a majority of that fighted (or is stupid). I can see damage dealers being 20% of a fight in def stance on many bosses though (especially Onyxia p3).
Also to add to the stance tracking: I think you need to consider stuff like execute (battle/berserk locked) to declassify someone from being in defstance as it’s one of the nearly guaranteed casts of a damage warrior, while Whirldwind might be disallowed in certain fights.
For druid, certain talents might help identification, if their effects present in the log:
Blood Frency (additional combo points on crit) -> DPS
Improved Shred (lower energy consumption) -> DPS
Feral Aggression (mostly taken for the increased damage on Ferocious Bite) -> mostly DPS
Primal Fury (generate rage on crit) -> Tank
Thick Hide (increased armor from items, might be hard to detect in the logs tho) -> Tank
Feral Instinct (increased aggro and imp. stealth, also hard to detect probably) -> mostly Tank
Pure tank has none of the cat ones I listed, but there exist a lot of hybrid specs.
Otherwise, except for Ony where your Maul won’t reach her in P2, Tank druids would spend 90%+ in bear form.
Another hint is the number of Fairy Fires cast, as it generates decent aggro in bear form and wastes a precious GCD for cats.
If you can change the threshold for each encounter, that would be great, as some fights have large numbers of tanks
Examples in Molten Core of 4+ Tanks: Majordomo, Sulfuron Harbinger
Examples in BWL of 4+ Tanks: Razorgore, possibly Phase 1 Nefarian
I had another idea of how to track tanks. Can you track Power Gains/Losses (mana, energy, rage)? If so, it would be possible to track how much rage a player’s Sunder Armor costs. If the player is specced as a Tank, they will surely have Improved Sunder Armor, making it a 12 cost instead of a 15 cost. Improved Sunder Armor - Spell - Classic World of Warcraft
Although the risk of using Improved Sunder Armor is that on single target fights (Magmadar, Geddon, Shazzrah, etc), the Fury/Prot specced off-tank will be considered a “tank” even though they spend the whole fight in zerker stance. Maybe that’s not the best idea.
If you can change the threshold for each encounter, that would be great, as some fights have large numbers of tanks
the whole idea of the stance tracking is that it doesn’t matter how many tanks a fight has. If you spend the majority of the fight tanking, you’re a tank. If you spend the majority of a fight dps’ing, you’re a dps. This majority should coincide with 40% defstance uptime (half of 80%), because many tanks go berserk/battle to execute. The threshold could still dynamically be reduced by sucessful taunts (immune taunts should be ignored).
. If the player is specced as a Tank, they will surely have Improved Sunder Armor, making it a 12 cost instead of a 15 cost.
This is an optional talent for fury tanks. The whole point should be to not rely on weak cues, but only on strong cues. A strong cue is something that definitely says you’re tanking and prevents false positivies and false negatives. Defstance/bearform is a strong cue for tanking (because you actively increase your threat and decrease your damage, which justifies a tank classification). Taunt/Growl/Mocking is also a strong cue for tanking. Taking the majority of meele hits is also a strong cue for tanking for single tank fights (but has threshold problems with multiple tank fights, incorrectly classifying in both ways). Everything else isn’t a strong cue really.
Has any of this been applied yet or are we still on the old system of classifying?
Hey guys, I got an idea that could help with determing who is tank and who is not.
A strong indicator of a player actually beeing a tank, is which consumables the player used for buffs. For instance, a Warrior, who consumed a Flask of the Titans can safely be recognized as a Tank, since this Buff does not yield a benefit for a Dps Warrior.
So if we can come up with a List of Buffs and Consumables, and highlight those that are likely used by Tanks and Tanks only (e.g. HP, Stamina, Armor, Fire Resistance Juju, HP Regen), we can add those as criterias for the System to recognize the Role of a Player.
Of course, this should not be the only criteria, but they are a strong hint in combination with some earlier mentioned methods.
Not really, all melee use similar buffs now. Titans is good for all melee cause you do 0 dps while you are dead.
but they are a strong hint in combination with some earlier mentioned methods.
i would even say they are not just weak hints, but might regularly give the wrong idea. On a regular low-consumable run, i’m maintanking with elemental sharpening stones, mongoose, giants, foritude, superior defense and blessed sunfruit. The only thing that hints at tank here is superior defense and maybe fortitude, though that is fine for dds too. Everything else are pure damage buffs, because damage = threat and tanking is about threat, keeping me alive is the healers job 
Is there an update on when this will be implemented? At least for bear it seems pretty easy to say if bear form is over 50% of the fight they are a bear. This is especially true for BWL as I tanked every fight but only got logged as tank for 4. Will we have to reupload logs after the update is out? For reference here is our log from last night.
Spell ids have been provided for warrior but nobody has done the work to get the Bear ones.
spell=9634
like this id?
See the earlier post with warrior abilities. Since I don’t start the fight knowing what stance you’re in, I will have to know you’re in bear form (or cat form, etc.) by ability use, so need the ids of spells that imply a particular form.
spell=9883-Maul rank 7
spell=9882-Maul rank 6
spell=9746-Maul rank 5
If we reupload logs after you change it will our specialization change?
Can you share the current metrics for determining what is tank/fury and bear/cat?