A phenomenon I've noticed, especially as I've started to do more and more heroics with better geared people, is that my DPS actually drops when I'm in a group of people who are similarly geared.
At first, I was quite puzzled. Why did my DPS drop so much, though I was doing everything I always did and in fact, had better gear than ever before?
It finally dawned on me (I, at times, have very thick skull). I kill through damage over time spells, mainly. That means that if the mob dies fast, my damage doesn't get fully applied.
This puzzled me as to how to rectify the situation. Do I continue to put all my dots on a mob, even though they aren't even all the way through half-done by the time it dies? Especially concerning is curse of agony, as it does more damage towards the end of it's application. Do I play 'shadow mage' and just spam shadow bolts?
I've finally hit on what seems to work best, given how fast it dies.
If it's going to do super-duper ridiculously fast, I toss a corruption and siphon life on it (or just a corruption), then whack it with shadowbolts. In the last bit of it's life (and the % of it's life I do this at depends, yet again, on how fast it's dying!) I toss through something that I've only recently respecced to get, Shadowburn, for some yummy instant burst damage. (I'll get to that in a second!).
If it dies relatively quickly, but not ridiculously fast, I open with an immolate, often while the tank is beginning to get aggro, corruption and siphon life, then shadowbolt it. The nice thing about being a warlock is that you build aggro slowly, initially. The longer a fight goes on, the more times your dots tick away, the more likely it is that without you even actively casting anything, you'll outthreat the tank. That's usually not so good. Thank goodness for soulshatter. :)
If I'm doing the most damage, because everyone else is doing next to no damage, then I toss the whole kittenkaboodle of dots on the mob. (or if I'm in a group with Bigpappi and the other DPS is doing less damage than the protection warrior...)
I'm somewhat of an odd affliction warlock, in the fact that I'm truly a hybrid. I don't have unstable affliction. (What, you gasp, an affliction warlock that doesn't use unstable affliction? Are you NUTS? Possibly I am, but I enjoy my fel armor too much to give up the points in it and I enjoy improved shadowbolt and bane too much to give up those points, either. Perhaps one day I'll respec to unstable affliction and lose points in something, but I will do as my friend Bremm is planning on doing, and I'll be making a science project of it, so I can see exactly how much damage more or less I do to any given mob) So I can only apply immolate, corruption, siphon life and curse of agony.
If I apply them in that order, as I'm sure many many warlocks already know, you can reapply in roughly the same order without any one dot being gone from the mob for any length of time (if you do it right, everything is applied as soon as it is cooled down.) (I highly highly recommend both necrosis and dot timers for any fledgling warlock. Necrosis is an organizational warlock tool that makes it so your hot bars are freed up for all the many things you really need out on hot bars, with openable/closable menu buttons for demons/fel domination summoning of a demon, self-buffs, curses/amplify curse, healthstone creation/soulwell creation/healthstone trade/healthstone use all in one button, felsteed/dreadsteed button, soulstone creation/application and the actual necrosis center itself serves as a lifetap button... it's yummy. Dot Timers is just a nicer version of something that necrosis also contains, whose name is somewhat self-explanatory.)
Anyhoo, by using the above, I've managed to keep up with fire blasting fire mages and rogues and all sorts of other 'ooh, lookit me killing it fast, yay!' people.
Something that for the longest time I spurned was Shadowburn. Back when I was way in Redridge and futzing around with all the skills, I took Shadowburn. And hated it. What was the point, I wondered, in using an ability that you burn a shard on, and unless you kill it in 5 seconds, you don't get a shard back for?
How foolish and young I was! You see, I watch those sneaky fire mages towards the end of a mob's life. They run in and dragon breath and fire blast and all sorts of INSTANT BURST DAMAGE.
How is a warlock supposed to beat that, unless they happen to have Shadow Trance go off just then and there? The answer, I discovered, is Shadowburn.
Now, on boss mobs, I tend to use Shadowburn whenever it's cooldown is up and simply keep in mind that I need to carry more shards than I normally do. But on regular mobs, I've developed my own INSTANT BURST DAMAGE. (hah, fire mages, eat my shadowdust! :). Is it the edge that keeps me up when I used to lag behind? Is it the changes I've made in my dot application?
Who knows. But damn is it fun to run up and *crack* Shadowburn! You have gained a soul shard.
So... to all those sneaky sneaky rogues and burst damage mages out there -- don't kill so fast, plzkthnx.