As a tank+healer main, I disagree. Any tank should have no problem (unless extremely badly geared) maintaining 2nd place enmity on this boss. Standing in front is a complete waste of healing resources. As healer, I've kept party-B tanks alive many times when B healers dropped. The true PSA here should be asking all WHMs to keep Regen running on the MT. That alone improves MT survivability by many times (unless there's no WHMs in the alliance).
A tip on add positioning: do not stand in front of mobs another tank is tanking! When two tanks want to have DPS AOE both their targets, and one or both of their targets have cleave attacks, you should stack the mobs, not yourself, so that you, the mobs, and the MT form a right angle or bigger depending on the cleave area. Minimize the damage you sustain, while forming a safe spot for the melee DPS, that is what you should be doing.
I can't count the number of times tanks drag mobs together and face their cleaves in every direction possible, forcing healers to spam AOE heals because all the melee plus all the tanks are all getting cleaved left right and center. You want faster kills? Then you should not only position the mobs, but also face the mobs properly, so your WHMs are not wasting time healing the DPS, but contributing with their Holy spam.
One tank can hold all the Unknowns and let DPS (and healer) burn the targets unhindered. It's a pain in the a** trying to cast spells with a mob whacking at you. And unless you have a DPS building enmity on the Unknowns, they're going to go for the healer. Someone is going to end up tanking them, it might as well be you, the tank, because...well...there's already another tank outside for the Wolfsbanes.
Ranged DPS and healers are actually great for meteors because they can take the hit while still dealing damage to whatever needs killing. Especially when clouds and meteor overlap. As melee you are of more use chasing clouds with your full arsenal than shield lobbing at them waiting under a meteor.
But you have stressed one thing that seriously needed stressing: pick up adds! Gosh I can't count how many times I got tanks who think they are DPS and ignore the adds...
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JP server here and probably 99% of runs in all Crystal Tower raids will naturally have the B tank being MT, and A/C leader will mention what they do before the pull.
Haven't seen trolls, although Bone Dragon gets burned about 70% of the time anyways and you notice most of the experienced healers will be ready spamming AoE heals if skeletons are making their goals. Teleporter spam I've noticed once or twice out of a whole month perhaps.
