For the last month my guild has been trying to get this. we have the 2 dps who go in on the first shadow zone click at the same time with the healer just healing. we stand there and wait 25 secs and hit the button before we die and we have yet to get the achivment. what are we doing wrong?
The more people who click it, the shorter the channel time. You can't do it with 2, it's (if I remember right) 30s channel time with only 2 people doing it, which means you'll die before it finishes. You DON'T need to kill the boss after doing it, so just send a bunch of people down at once, get achievement, wipe, come back n kill boss ;-)
2 people makes it 15 secs or so says wowhead. me and my buddy stand there and clicked the button. then we watch the timer go down for 25 secs and have not gotten it yet.
We did it on our first totem. 2 DPS and the healer go down. The 2 dps immediately go to the totem and start channeling and the healer heals us up. Once were healed up the healer comes and channels. We did this on one attempt and still got the kill. Good luck.