Now that I am pretty actively playing all three classes (dps, heals, tank) I am rapidly building more appreciation and more awareness for each class. Now I am by no means pro at any class, but the majority of my experience is as dps (ranged and melee). I have absolutely been guilty of unloading on mobs with little regard for kill order or aggro (sorry!). Due to my periodic (very, very rare!) errors, I have decided to write a brief list of pug/instancing tips for the new player (or the seasoned player who forgot!)
Tanks1. Relax. For the most part you control the pace of the group. Don't let group outpace you, but don't outpace your group (especially your healer!). Being on a different page from your healer is definitely a bad thing!
2. Please let buffs get done, mana and any other prepping before your go running off to the next fight (i.e. check mana bars...pay attention!).
3. Keep on eye on your mobs. Don't get tunnel vision. Your healers or dps may not let you know that they are being chewed upon.
4. If you'd like something done in a particular way, please let the concerned party or parties know.
DPS1. Relax. Giving the tank 2-3 seconds to establish aggro is absolutely not going to make a bit of difference in your total instance time. If you don't have the extra 35 seconds to spare, maybe you shouldn't be playing right now!
2. Do not outpace your tank. If you pull something, you better be prepared to tank it yourself. Your tank may or may not help. Your healer may or may not help. If you do accidentally pull a mob, or entire room, apologize. Easy.
3. I know you feel your epeen size is directly related to your dps, but the truth is, it's an inverse relationship (he he). It's not about recount. If you ramp it up, pull aggro and die, who cares if you were doing 6k dps. Staying alive and doing great overall damage is more important. The whole group staying alive and having a good time is even more important!
Heals1. Relax. You'll do a better job and have alot more fun!
2. Let your group know what you need. They can't read your mind.
3. Sometimes people forget. Friendly reminders are nice!
4. Have whatever supplies you may need. Mages may not be there to be your personal drink dispenser.
Group
1. Relax. It's a game!
2. Be aware of others. If you queue, please be an active part of the group.
3. For the most part, if the floor on which you are standing is currently not the same color (such as purple, green, red) as most of the instance (particularly if mysterious little red numbers are scrolling up your screen around you), please
move.
So there ya go. Some simple tips to make everyone's lives a little easier. Feel free to add any tips that you feel may be needed as well!