First, sanguine strikes is the iron maidens < 20 % hp ability from marak (all dmg you take as a tank from marak will dmg the raid)
I have heard interviews from pro guilds, where they talk about how op monk is in that phase, since the raid will take almost no dmg.
I had to handle it as a protection warrior. The biggest problem was, when shit becomes to get heavy, our boat group would die due to sanguine strikes (we play the, 3 ship go into p2 while ship 3 is going on, tactic) killing them. So i was trying to find a way how i could minimize the dmg the boat group would take at the beginning of the last phase. And i came to the conclusion, that no dmg at all is the best (i m so smart), so i did following:
call for a hand of protection.....well in the first place you d call me stupid, you d say: you will loose aggro on marak so whats the point idiot? But what a lot of tanks (and people overall) don t know, as long as your taunt is active, the boss is still "forced" to attack you, even tho ur immun to physical dmg, so i pop vigilance and just keep on taunting marak through the hole time hand of protection is active on me. This lets me tank marak for 10 seconds while i m immune, after that, i ll obviosly have a caped "clarity of will shield" on me, and have like 10-20 seconds left to tank marak until she dies. You ll have to tank marak for like 20-30 seconds ovreall until she dies, so 10 seconds of beeing completely immun is huge. You ll have (or should have) a caped COW shield at that point and all your cds for the last 10-20 seconds until marak dies left. Our raid took like 800 k dmg from sanguine strikes in our first kill. But honestly, you should be able to reduce the dmg your raid takes from sanguine strikes to absolutely 0 with this, if your disc keeps on spamming COW on you.
I have checked like 20-30 logs from top guilds, and i haven t seen a prot warrior use hand of protection + vigilance like that. But on the other hand i have heard interviews from top guilds, about how OP monktank is for that specific part in the fight. If you reduce the dmg from sanguine strikes, the >20 % phase is kinda trivial, this is the main source of dmg at that point, and the thing where most guilds (imho) struggle on.
So i just thought this will maybe help some prot warriors to handle sanguine strikes better. Even tho monk thank is probably still better in taking marak > 20%, we still have a pretty good tool in our arsenal, we can facetank a boss while beeing immune for 10 seconds, no other tank can do this (besides druids if they change talents for it).
Hf