Unfortunately, I think you'll find most players DON'T understand or know what's going on other than spamming spells and stabby stab, whack-a-mole.

I think the unfortunate truth is that, unless you've played a healer or a tank for any significant amount of time, you have a very shallow sense of how things work and should work tanking.

From my experience, changing rolls in a raid can and does change the perspective a fair bit. One's also left facing situations they either don't pay as much attention to (unless they're a raid leader of course), or lets just say aren't thinking about.

In TBC, I went from raiding on a hunter, to a rogue, to an ele shamy; and even though all are DPS roles, I get a sense of this first hand.

When for instance, as far back as kara for instance, doing Opera, as a hunter I'm not overly concerned about the interupts on Juliane. I'm aware that she can heal yes, I know to switch targets (something the rogue kicking should never do), yes, and to keep an eye on the relative hp lvls of both mobs, and be ready to switch if either a. it's called, or be, I see a problem and it's been forgotten?

OK, so all good, now was helping in a reform to a prior guild of mine, and my alt is their ONLY ROGUE. So now we're up to Opera again, and it's Romulo. This time, it's on me. If Juliane heals, and they die at the wrong time, it's on me. Did I know about it? Yes, and came in knowing well enough to know "ok, this will be different". This is NOT to say experience isn't necessary. For instance interupting the right spell is important, and keeping an eye on it. Once one gets a sense of the caste sequence, one can even throw in an attack, and still have energy left to hit the eternal affliction. And believe you me, the first go around eternal affection and eternal affliction can look very similar on the cast bar, the first go around. Make that mistake on the first go, make note of it, and watch it more carefully next.

Going through mobs, bosses, etc from range to melee, I could see "OK this is comming", but that isn't the same thing as actually doing. A flip side to this (and this is an article on tanking), from the hunter's perspective, one can be paying more attention to pulls (one is asked to MD of course), or the pre-TBC method of running up, range pull mob, run to tank and FD on them as they are waiting to taunt off. The rogue isn't interested in this aspect of things. I mean, how often is a rogue asked to use their lil pea shooter to grab a mob, and vanish on the tank? :s

So now, I brought a shamy through raids, though this time my rogue got further (ssc/tk, vs up through gruul's), and again there was a shift from melee to caster dps, though having played hunter, range isn't totally new. However caster DPS is a lil dif again, (mana pool considerations for instance, and though a hunter has them, they do have viper sting for instance, etc). Spells are also in the main not instant, unlike many shots.

And this is just on the dps side of things, in switching DPS roles. And yes, there were many mobs/bosses where I was like "OK, this is going to be interesting" and knew it was comming. But knowing what's ahead is only half the battle...

It is also absolutely correct, that on mobs, there are specifics with pulls that the DPS isn't paying careful attention to (and I'm no more innocent of this either). For instance, I know that in ramps there is concern with mobs fearing. It's necessary that they get pulled back, I let the tanks handle it. Could I tell you, and specifically remember the names of which mobs are doing this, not off the top of my hand. If you want to kill some mob first, you have to know what it's called to mark it however; and just knowing "one of them around here does it", doesn't tell you which to mark, etc....

So have I done any tanking before? Yes, I did a lil on my warrior around SM, and I did some in several instances on my druid while lvling through outland. Mind you, where I had a friend who was lvling a hunter alt in there (his main was a feral tank), there were more then a few moments where I was asking him about the pulls in PST. The rest of the group didn't see it however; and I still can't say I'm 100% sure of all the marks...