Helping healers help us
While the idea of assisting a squishy priest or tree druid would normally disgust me, we're often forced to partner with healers in order to succeed. It's our job to kill the boss before it wipes the raid, and it's the healers' job to keep us alive long enough to do that. If you increase your DPS, you are shortening the total length of a given fight, which actually makes the healers' job easier. Outside of simply applying damage, there are a few other things we can do to assist to healers when they're faltering.
Feint is right at the top of that list. Feint will cut down your damage taken on every single Dragon Soul encounter, and with the Glyph of Feint, it doesn't cost you more than a GCD to use it. In fact, Feint not only allows us to help the healers by taking less damage, it also enables us to deal more damage since we don't have to run away from bosses like Morchok when the damage gets too intense. Cloak of Shadows works in a similar fashion. Cloak allows us to negate incoming magical damage and enables us to continue attacking our targets, like Deathwing's Elementium Bolts.
Outside of Feint and Cloak of Shadows, we really only have Recuperate available when it comes to either healing or reducing our damage taken. Recuperate's healing is pretty poor, and as such, you shouldn't bother using it for its HPS. Subtlety rogues will keep it rolling to benefit from Energized Recovery, but assassination and combat rogues are likely better served using those combo points to make the boss die faster.
Tanks need love too
I have a very specific priority system for choosing my Tricks of the Trade target: another rogue, a tank, someone I'm trying to gank by sending mobs to them while they're AFK, and nobody. If I know there's a pack of adds coming up soon, I'll save my Tricks of the Trade to help the tanks pick up aggro. I always open fights with Tricks on my raid's main tank to ensure that everything goes smoothly.
After the developers normalized interrupts by giving every melee classan interrupt ability on a short cooldown, tanks have started shouldering the burden of interrupting bosses. While none of the bosses in Dragon Soul require interrupts, it's still an important skill to have. By working out an interrupt rotation with your tanks and other melee classes ahead of time, you can ensure that any caster is locked down completely.
Sometimes, DPS is secondary
In Dragon Soul (and other raids before it), there are moments when we're actually not concerned about our overall damage. I'm not talking about minor inconveniences like swapping to a new target or running to an add, as those are very common. When we talk about DPS being secondary, this tier's example encounter is the Spine of Deathwing. For portions of the Spine of Deathwing encounter, you won't have any really good targets to attack. If you're waiting for your low-HP Amalgamation to build up stacks of the blood debuff, you can rest for a bit.
In fact, in most situations, you don't even want to use your cooldowns to nuke down the Amalgamation. The Amalgamation might seem like the boss-style mob of this encounter, but the truth is that there's no big hurry to kill the Amalgamation quickly. Most raids could survive the Amalgamation phase nearly indefinitely if they had to.
The difficult part of the Spine of Deathwing encounter, especially on heroic mode, is destroying the Burning Tendon before it reseals Deathwing's armor. Everything we do on the encounter needs to revolve around that goal. The blood and Amalgamation are secondary targets, and as such, we shouldn't be using cooldowns on them. They're just trash mobs blocking the way to the real boss, the Burning Tendon. You might fret when your DPS on the Spine is low when compared to other encounters, but success trumps DPS every time.
Doing awesome is better than looking awesome
If you wanted to look awesome, you could pop Blade Flurry, your Kiroptyric Sigil, and Adrenaline Rush on a big pile of blood, and your DPS would be amazing. You'd parse at the top of World of Logs. Your raid might wipe, though, when the Burning Tendon appeared and all of your cooldowns were unavailable, and so it resealed the armor plating. The success of your raid is worth sacrificing some of your DPS by holding onto your cooldowns.
You might think that I'm cherry-picking one encounter from this tier, but this type of situation happens quite often. Many raids halt DPS on Warmaster Blackhorn until Goriona takes off to prevent tank deaths. Subtlety rogues can pad the meters by using Fan of Knives on Yor'sahj's adds, even though they're better handled by fire mages and arms warriors. Saving cooldowns for XT-002's heart phase was commonplace in Wrath.
In fact, DPS classes used to rein in their damage all the time in vanilla WoW, when threat was still a nebulous force and Omen was but a sparkle in Xinhuan's eye. Holding back is not something that comes to rogues naturally, but we have to learn self-control if we want to succeed.
Sneak in every Wednesday for our Molten Front ganking guide, a deep-dive into the world of playing a subtlety rogue -- and of course, all the basics in our guide to the latest rogue gear.