Ok, we have done like 30+ attempts on heroic yesterday, with 3 healers doing at least 12k hps+ and even using 4 healers (4th being disc priest) and every1 of them doing at least 12k hps, but disc priest doing enormous amount of absorbs as well. For some reason our healers seems to be stressed a lot since it's HM and they forgot how to heal ppl to 10k hp so they won't die though...
Anyway, we did 11% wipe with ppl being at 20-30k hp before we entered second phase, so obviously our fault. We could've made it as I didnt die as prot warrior until 11% and 2 out of 4 dps were dead after 10 seconds of 2nd phase tho. Apparently chim going into second phase HAS been fixed, but no.. i cant see it being fixed as he started 2nd phase at around 21.5% and that just fucked up everything as we were healing to full after the massacre and specially waited for feud to finnish at 22% of his HP.
As for intervene it works perfectly fine. We are doing it with 2 tanks and I always intervene paladin once he is about to take double strike after the feud while having 4 stacks of break. There is usually two things happening : he takes 2 strikes anyway but the dmg is reduced by 30% so it usually saves him. Other thing is when i delay intervene and just use it 1-2 seconds before the actual double strike (not when the warning comes) and that always for some reason makes me take 1 hit which would never kill me ofc and him taking one hit and that obviously won't kill him too. It's random for some reason, I was checking my latency each time this happened and it never got higher that 150 ms so I don't think it might be lag related.
Anyway works fine either way and helps a lot keeping both tanks up and running. I would also suggest starting fight with prehealing the break tank so warrior can intervene and palading won't have to waste time taunting and building aggro, that will just simply help dpsers do higher numbers at the start of the fight.