No mention at all of Frenzy or Ember Flare ("an AoE about every 10 seconds") for phase two.
Ember Flare which deals approximately 20,000 fire damage per target is cast every 6 seconds.
Frenzy is cast every five seconds, increasing her damage by 5% per stack.
Those two mechanics combined make it impossible for "this just has to be healed through". I'm sorry but when you get to the average kill time on worldoflogs of just shy of 7 minutes, you are dealing with about a 30 stack of the buff at that point and that 20,000 damage every 6 seconds isn't 33,333 DPS to the raid, it's 83,333 DPS to the raid at the end. Now tack on the damage your tanks are taking. Your comment there reflects a very naive nature to the amount of damage being dealt with. This is unhealable damage levels for three healers, it can only be managed by chaining cooldowns. You can't just heal through it, it's not possible to maintain throughput levels that high. Unless you outgear the content, however as you outgear it since the boss will be dying faster it will not be necessary to heal at these levels because Frenzy won't stack nearly as high.
The Widows Kiss is a healing debuff on the tank which is why you tank swap, however it also causes you to deal fire damage to nearby players. You made no reference at all to this ability causing damage.
Also a video at double speed doesn't help much in terms of perspective.
"In anything, if you want to go from just a beginner to a pro, you need a montage." /w TankSpot WTB Montage for Raiders.