DRG, trying to take the trash out.

First, the problem: I feel worthless in groups unless we're killing a (single target) boss.

My damage appears to be about on-par with the BLMs and SMNs on a single target, but as soon as there is two or more, I feel like a wasted DPS slot.

Ring of Thorns or Doom Spike spam barely scratches anything, although they are technically the highest potency attacks I have once there are 3 targets, spamming them will quickly run me out of TP, even while using Invigorate. So that's a bad option, but it is an option.

Are there any others?

Those MJ jumps are too slow, however patch 2.1 is making me excited. Also always combo RoT.

Hang in there pal! If you feel like you're not contributing enough to the group, cross-class in mantra from the monk set!

Don't worry though, most of the damage you deal is frontal loaded! When everyone's DPS is up to par and the gear is better, Doom Spike becomes AMAZING aoe damage. You might run out of TP, but that is what invigorate is for! My recommendation? Single target until you have 5 or more targets to AoE!

Seriously though, I felt the same way until everyone's gear started getting better. Mobs die a lot faster, so that means the guys who do the most frontloaded DPS will be on top!

tldr; just wait

But dragoons just look too god dang cool to not take along, other are just bonuses!

try to take it to the flank then RoT. then, if the target is about to die switch to the flank of the next mob then use RoT again. I assume all aggro is on the tank. so they are quite near to each other. good target selection and positioning is needed when using a DRG for its aoe. because we can say their AoE without a combo sucks add it with the high TP it consumes.

and don't feel you are worthless with others out-dpsing you. at the end of the dungeon, it's not the dps you deal that matters it is how you play and finished the dungeon.

Dragoons aren't really good in continuous AoE, it's more like a "burst" phase. At the beginning of the fight you bring up all the buffs/debuffs, then use Dragonfire Dive+Heavy Thrust+Ring of Thorns+Doom Spike for massive damage at all of them. Great for weak adds/mobs situations, not so great otherwise. We are meant to focus on one guy and nuke it with high potency combos/jumps, and while we do have a few AoE tools we shouldn't rely on them too often.

Except Dragonfire Dive, with its sweet 250 potency. While it can't be buffed with Power Surge, it still is the strongest jump we have when there are multiple enemies - and even while in single target, is only surpassed by Vorpal thrust and buffed Jump. Seriously though, buffing Dragonfire Dive with Power Surge would be OP. Aside from this rambling, Dragonfire is your best bet while taking out multiple trash mobs, followed (very afar) by Doom Spike if you can align the enemies and a combo'd Ring of Thorns.

Um, for generic 3-mob trash in dungeons, use HT-ROT over and over. DS is more DPS, but much less TP efficient and if you continuously pull trash, you will bottom out on TP (hell you might even bottom out on the first pack of trash depending on your gear and the other DPS.

For 2 mobs, stick dots on both (CT chain and PH).

Doom Spike is only really useful for 5+ or for AOE immediate burst. E.g. WP speed runs or Coil Turn 4. Very rare to use it otherwise.

You're not meant to do good continuous AoE.

You are single target dps. Blm is better with aoe. So if you don't feel you out dps them, work better on your rotations for single target, and get more pieces of upgraded gear. Drg scales pretty good with more gear.

BLM and WHMs are the only AOE DPS that DPS harder than a Dragoon.

Dragoons simply can't sustain it over long durations.

Learning how to efficiently AOE DPS is important to Dragoon-ing in general.