In H25-man, just as in normal, there are two crystals. Melee assigned to one, ranged to the other. You could try to assign who takes the torment-beam when, but it will almost always get screwed up as torment spreads. We ended up not assigned roles but just relying on two different vent channels to call out who was taking it real-time. Melee also had one big rule: if you weren’t tormented, stand as close to the boss as possible. If you were tormented, max melee range for you!
Don’t gravitate too much to the outside of the boss. It’s tempting to run out to the corners because you’re less likely to infect someone, but it means the shard could spawn in the corner, quickly shoving the entire raid into one corner and trapping people.
At intervals there is a linked attack (Countdown, much like Blood Queen in LK). Both linked people have to run close enough to each other to cancel the spell. Theoretically you can be close enough to drop Countdown, yet far enough to not spread Tormented, but I have never, ever seen that happen. Tormented always jumps. ALWAYS.
Once you figure out a communication style that works for your raid, to ensure people always know who is taking the current shard, you’ve got the fight. The key is really keeping from tormented spreading needlessly.
Re: communication and vent. We had a melee channel and a ranged channel. Healers and officers put a shadow in one or the other. That way 85% of the raid could only hear what was important to their group. If melee were shouting to someone to take the crystal, ranged was free to shout the same in their channel with no interference.
I’m going to be honest, we never did get heroic Baleroc in 25-man, only in 10-man. I think sometime after the 80th wipe we switched to 10, at which point it was like archiving a zen state and the fight became super easy. Suddenly there was all this room to move. Before, you turned your camera to the left and infected four people with tormented. Now, now you could dance the hand jive around the boss and never touch another person.