Am I able to not tank?

My three 80s are all tanks. Next highest is my shaman, who I level mostly because I feel obligated to not leave him behind, being my namesake and all. Somewhere down the line is a feral druid who is moving up fast.

Apparently my guild needs rogues and mages. I have a currently 72 rogue. Assassination is a lot of fun, managing debuffs and my buffs and all that. What does this add up to? Level the rogue, gear it up, and start raiding with it. What could possibly be the problem?

I'm used to tanking. Or more accurately, I'm used to being possibly the most important person in a group. Second if it's a raid. I am leader most of the time, I do all the pulling, I get to yell at people and act important. DPS can't do that so well. They're expendable. When they mouth off, they get booted, at least if I'm leading. What tank is going to be talked back to by something as low as a DPS?

Oh sure, I managed as a warlock. The first time was when I was badass CC and often was more important than the tank. That was in addition to my impressive damage. In BC my warlock was incredible at AoE, besides, I really loved the seed of corruption animation. I remember tanking for three warlocks once in SL, it was beautiful.

But good DPS are important, right? Sure, go ahead and think that. When I'm in LFG I can't select the "good DPS" box, there's just "DPS". I could add in my stats, but I look down on people who list their stats, they look insecure, and a bit naive since other classes might have no clue what are good stats. Listing DPS numbers makes me laugh. The only time I ever thought it made sense was when someone listed a range; and then someone else flamed him for buffs accounting for 25%+ of his DPS. I thought that other person was an idiot to not realize what 3% damage, 3% haste, 10% AP, 10% agi, etc. will do. That stuff adds up fast.

But let's say good DPS are important, I don't know if I'm good. I do okay on my paladin, maybe, I don't run meters, but bosses die, so at least I'm not doing negative DPS and making the raid worse. Which reminds me, paladin DPS is incredibly boring. What if I'm bad at DPS? I don't have to worry about being good or not as a tank, tanking is easy. Wear decent gear, press buttons, mod gets angry, somehow it dies, and I get loot. Easy.

A rogue might get me back into raiding and heroics and all that, but will it destroy my e-peen?

P.S. Please heal me when I'm fighting spell flingers in Ahn'Kahet. Yes, I know, I should assist the tank, but you do not want it getting off shadow blast.