Regarding a few things being mentioned in this thread regarding the fight.
Firstly, we were having a problem getting the Lava Pillars in "melee." It was helpful to have someone call out a "reset" when there was 5-8 seconds until the next Lava Pillar. Upon hearing the reset, any raid members that were out a little bit DPSing the adds, knew to snug right back into melee range. That might help some of you that consistently have the Pillar spawn in melee.
Secondly, we were having trouble taking the adds out in time, even with 4 ranged on them. What ended up working for us, was having the Rogue help us out too. Our rogue was Assassination, and so he had 2/2 Deadly Brew, meaning he was auto-applying Crippling Poison to everything as well. As soon as the Lava was on the ground, he'd pop out of melee and get ready. As soon as they were spawning, he put ToTT on one of the ranged, and FoKd until Tricks dropped off. That strategy trivialized the fight, and removed the need for a ton of AoE snaring, and allowed our ranged to focus more on just burning them up.
Also, we only had an issue with the post-spike aggro reset once, and it was one of the Shadowpriests. I started calling out for priests to Fade when his head came up, and it became an easy kill.
Great video guide, cheers and good luck.