There are some tricks to getting this.... and I'll cover a few.
First, having a pally tank is HUGE. The first boss TRUCKS the tanks... but also leaves a stacking bleed debuff called impale. The tanks should switch at 2 stacks, with about 5-7 seconds left on their old stack.
After Sapphires (pally tank) and I would each have a turn (I would go first), I would take the third rotation, and he would take the fourth. Instead of me taking the fifth, he would stack his debuffs to 3 and then immediately bubble them off. I would get aggro for a second and he would taunt it back.
In this scenario, instead of the healers having to heal both the tank getting slammed, the bleed AND the other tanks bleed, his stack would be gone, mine would drop off and I would taunt when Sapph got to 2 stacks again. I would generally get one more and then it was over. I would ALWAYS use indestructable potions before the pull, as you are not in combat until right before the doors open and the boss runs in. Then use one later in the fight. I popped my trinket on my first turn....., used last stand on my second one and used shield wall on my third. This allows for last stand to be back on the worms, about half way through the first "up" time (assuming you have glyphed and talented both 2 min cd's).
Second, we two healed this. I realize that this is a COMPLETE nightmare for the healers, but our three heal attempts lacked the dps to finish the event. Deeder (priest) went disc, which is big because you get preventative heals and then you need an AOE healer (we switched between Saccapoo and Khak, both resto shammy's).
In phase II, we have the tanks stay with their respective worm, even after burrows (little trick, if you have the hunter use hunters mark, you can see where the worm is going while underground and we found that helpful). You know which is yours because if you had the worm that was rooted before, you now have the one on top and being kited. Tank them near each other, and if anyone gets the poison debuff EXCEPT a tank, they are responsible for running toward the person with fire. Generally, when the other tank got it (me), Sapphires would strafe to get it to me. We found that the whirl damage and the fire damage that was an AOE to the rest of the group was not that serious, so we built a strategy ignoring these abilities. You dont have to kite the first worm a lot since Acidmaw is dying first, so there is no melee to worry about (different if you have split dps and are going for acheivement). The second one you have to kite, but ours died within 20 seconds of the second "up" phase.
Phase II is about survival. You have to keep everyone alive. If anyone gets sprayed with the breath weapon besides a tank, its a death. Druid buff is strong here for resistance. Also, when Acidmaw dies, Dreadscale trucks so you have to really be on the tank for heals AND you have to avoid incidental damage as any distraction for the healers is bad news.
Generally, we have about 15% left on Dread when Icehowl would show up. Stay on the worm and the other tank gets Ice to the center of the room.
Once the worm is down, Phase III is a straight burn. We noticed that after he hit the wall three times, he enraged, so I dont know if its a straight timer or if he does his wall thing at specific times. After the third time, he will enrage and you wont have a ton of time to get him down. We saved bloodlust for when he was stunned in phase III. Shattering throw, etc.
A trick to moving in time that we used is this. Point your camera along the wall and hold both buttons down. When he lets you go, you wont go that exact direction, but if you move the mouse at all, it will adjust you and you can maxumize your escape time to avoid the charge.
We found that if you keep everyone alive and you can avoid the crashes, you can have him down before his third stun phase (as we did last night). If not, you will really be pressing to beat the enrage timer.
We tried Jax a few times and found him to be MUCH easier.... just a matter of getting the practice on it. Blizz did a good job of tuning these things.... I'm looking forward to finishing it!