We send me (Enh shaman) and a rogue up there...though I am the only one that is guaranteed to a) kill the thing and b) survive...when the rogue dies (notice I didn't say if) we send up our frost mage
What I do:
I do the ODD belts.
Buffs: Lust + Em + Trinket/cloak start of fight procs + prepot
I get up there as soon as I can and get as close to the "incoming" gate as possible drop FT and wait for my target to get into range
Then I'll swing my camera around, backpedal and keep smacking it....the hit box is big enough that even if you have to run tot he side of the belt you can still smack the weapon
It should die (with decent procs) right after last set of dodge bars then I attempt to get to the out pipe without using any running cds (maybe ghost wolf) otherwise wait to get pulled out.
Then as soon as I hit the ground I pop PFE and go to work on boss
This one can get tricky so I'll use Ascendance if I need it (can usually tell by 2nd dodge bar if it isn't down to about 45%)
We usually have the boss at <20% here and I'll just stay and burn it down....if not I go up there with EM and Spirits off CD and will dps my ass off to get this one.
I appreciate all the replies. We've been working on this, and I've done both sets of duty.
After a bit of practice, the belts became easier and easier to do - trick was just learning the beam patterns, relative to which add I was killing. The bigger trick is still managing dps cooldowns. I'm sure if I can ever get heroic AoC to replace my flex AoC, that it'll be a noticeable improvement, as well.
For boss-tunneling & mine duty, I can see and agree with the argument that says enhancement is better on the boss. My overall dps/damage is significantly higher, BUT so is anyone else's who isn't splitting off of the raid, to do belt duty.
The best attempt was us getting the 3rd belt down, and the boss to about 48%. We're about 4 or 5 nights into attempts, so I'd guess that's decent progress. It seems that where it all goes to shit, for us, is when we don't burn the mines down ASAP.