I doubt I'll ever have that earring, lol
Good DRKs are invaluable, tanking, zerging, or just plain throwing out numbers, average darks or anything less aren't worth their grain against average<other job less difficult to fuck up for those incapable types>. That goes without much saying, I suppose you can say that about a good handful of jobs, but if a DRK is bad, they tend to be really bad.
Other than zerging drk doesn't do anything as well as other jobs can. Tanking is debatable but I think most people would rather use sam due to access to a much wider variety of PDT gear. As far as general DDing goes its inferior to an equivilent war or sam and too many people have delusions about the job (zomg my shitty absorb spells and drain make me a hybrid class).
Its just a mediocore DD until you give it full haste/hp and a Mkris/Kclub and zerg.
It's just a matter of them having those tiny ass niche times when they're useful, to give them the fair perspective that they can, if required, pull off the situation at times.
I don't necessarily like DRKs myself, but I wouldn't shrug off the entire job without saying, 'well it can do this if necessary', but I suppose I'm taking the term 'useless' too literal, and everyone just means that it's not useful as certain other jobs.
If geared well, DRK can pretty much excel in any situation, except for DD on some of the mobs that you can't consistently melee (SAM and RNG on Tiamat/Khim come to mind).
For average damage-dealing situations in places like Einherjar and Dynamis, it's about second-best next to SAM and about equal with WAR.
However, similar to BLU, DRK shines in its versatility - with the right gear it can tank/kite many times better than its other DD counterparts when the opportunity arises, and it can even provide mediocre support in a manaburn situation (Strongest Bio II in the game, Abs-INT/MND for lower magic resistance/defense, ~480 damage Drain II's and Stun).
War doesn't come second to sam until you move onto the harder stuff where the 1 hit WS with attack bonus really starts to shine. Other than that I would say a good war/sam is pretty much untouchable for merits and einherjar. I would definately put drg in 3rd place above drk with drakesbane now available.
Drk can kite well yes but I can't think of anything that gets kited now, and for most tanking situations, unless you are unable to keep hate through damage then sam is going to do a better job with the proper gear sets.
WHAT LOL
That's about as beneficial as a WAR being able to tomahawk. I'm almost sure that SAM can outperform DRK at everything that doesn't involve SEBW or kiting, since SAM still doesn't have movement speed gear (-_-). SAM/NIN could stay alive longer than a DRK, has access to far more PDT- and MDT- gear, and can make anything look retarded on birds if you want to bring this down to merit level.
That being said, I still regret picking the one job in the game that can't wear movement+ ^^b
DRK won't excel in every DD situation, purely by the definition of the word excel. It will always be greatly outclassed by WAR and SAM unless in a zerg fight. I leveled the job thinking I could make it into a powerhouse with the gear I'd have ready for it at 75, but the damage output was just disappointing compared to other jobs. Luckily, I acquired a Kraken Club, so all wasn't lost on leveling it to 75 =].
And from my experience, WAR is easily at the top of any average DD situation, followed by SAM, and trailed by DRG and DRK by a good amount. SAM really starts to shine when a mob's defense is severely inhibiting damage from WAR's multi-hit WSs, e.g. JoL... although WAR/SAM with 2 brds on JoL is pretty damn nice.
I think JoL is probably one of the places where drk shines to most (outside of zergs), if you can get 1.5k hp then you will reliably survive a boosted melee attack and with dread spikes up you can make it kill itself.
I wasn't saying that DRK was GOOD for manaburning or something ridiculous like that - I was simply saying that when you're doing an event, and you run into something that takes little to no melee damage (or on which melee damage isn't worth the risk), DRK can at least perform basic utilities such as providing a stronger DoT than BLM or RDM, an extra Stunner, and strong Drain/Drain II. Also, Absorb-INT actually helps quite a bit - I'm not sure how effective Absorb-MND is, but I use it anyway to lower resist rates.
From solo/duoing lower tier ZNMs and Sea NMs such as Ix'MNK/Fortitude, I know that my Absorb-INT will up the damage of the next nuke significantly (+10-20 damage on my SCH friend's Helices, which adds up to a significant boost over the duration).
Put a SAM or WAR in any of these situations and they have to thumb ass while the mage jobs do the work.
As for merits - WAR/SAM will outclass DRK every time if both are equally geared, and probably SAM too. But, DRK will definitely outdo a DRG, WAR/NIN, or MNK any day, unless you're parsing DRK vs. DRG on Birds or something with Piercing bonus. Next time you take your Polearm SAM/WAR to Birds you have to remember to take off 25% off of your parse results!
I have WAR, DRK, DRG, and PLD leveled. Of my melee jobs, all four are well-geared. In terms of straight damage, I'd tier them like this:
WAR/SAM > DRK/SAM > WAR/NIN (with Ridill) > DRG/SAM.
And this is with merits on Scythe/Sword, so maybe with Polearm merits DRG would step up to equal footing with DRK, I'm not sure. But I have outparsed my share of strong DRGs on Mamools, including a Gungnir, and I definitely don't see DRG doing equal damage to DRK at that camp. WAR/NIN with Ridill still has its obvious merits in survivability, as DRK/SAM and WAR/SAM both require more aggressive support if you're going for straight-up damage.
Finally, DRK can certainly tank better than classes that rely on damage to do so simply by nature of the job - SAM, WAR, or MNK would require doing damage to keep hate while DRK can mostly rely on the CE from spells similar to PLD. In a lot of cases, meleeing monsters continuously isn't really a good option. Obviously there are other cases where SAM/NIN DOES tank much better than DRK (Salvage chariots come to mind; even though DRK CAN tank them, SAM/NIN certainly is much more effective), but a SAM can't tank something like Tiamat on the other hand.
It really is a much more versatile job than any of the other melees that I've played, and I'm pretty sure I've played them all (except THF).
Keep in mind Perdu Sickle is 10% better than Tred. Scythe.
crunch the numbers bro