Unlike the first time kiting 10man Gluth adds, I didn't have a second Frost Trap (and no totem/Frost Nova etc either). Not only that, the buffage was lacking - no pally or mage. I was completely on my own this time. Hooray, a real challenge!
....Unfortunately, it was a complete failure.
Basically, I'd underestimated how fast I would burn mana, and was forced to switch to Viper soon after the first Decimate.
Now, if you're standing still and DPSing hard, Viper fills your bar fairly quickly. You don't notice your DPS drop in the brief time that Viper is up, and you're back to full strength without any issues.
When kiting and picking up adds, however.... the difference is glaringly obvious. I could NOT pull the adds off our tree druid no matter what I did while I was in Viper, and even though I switched out ASAP, it was too late - I was behind on aggro. I desperately tried to get some Steady Shots in, but the zombies promptly whacked me for standing still and we wiped (our DKs tried to pick the adds up, but with no way of slowing them down Gluth managed to eat a whole bunch).
So... not my greatest moment as a hunter.
However, I decided I'd do it differently for round three: Kite the zombies pretty far back in the room, switch into Viper as soon as Decimate hit, and let the others worry about the zombies while I worked on mana regen instead of spamming Volley as usual.
The zombies died, I had enough mana to keep aggro on the next lot of zombies, and we were dancing on Gluth's corpse within minutes.
I don't know if I'll have time for round 4 this week or not, but at least I know the only thing I have left to work on is not getting hit. Perhaps a little more use of Deterrence is in order....