The way I do it is pop my fire eles, heroism, trinket EM/CL. Blow everything right at the start.

I can usually get him to about 20% ish +- a little before he incites chaos. Then it's just a matter of taking the remaining shamans and tearing him up afterwards.

I wouldn't really worry about trying to tank him TBH. When I run SL, I use fire eles on the second boss and earth eles on the last boss. The timers are spaced out in such a way that you can farm the instance without breaks and have eles up for the bosses you need them on.

If you're talking about heroic though, I really don't know. I roll with four ele shams btw, no healer. I think that might be the difference between us, just getting him as low as possible without worrying about holding aggro or anything.