Let me guess.
That BM hunter is using a scorpid pet?
Freaking scorpid are dealing like 450dps alone. (900 per tick poison dmg)
Its actually sort of an exploit.
Just pop TBW and all AP trinkets then you activate scorpid poison rank 4. (rank 5 doesnt work coz it wear off fast and and have longer CD)
As long as you maintain the stack of scorpid poison thru out the fight, the scorpid poison damage will remain the same even without TBW switch on.
Blizzard already nerfed it badly. I mean very badly.
I tested it on PTR realms. It only deal 220dmg per tick at 2600AP now.(Pop trinkets n Orc talent)

QUOTE
but that's just cos he's skilled. one of the rare hunters i've ever seen
BTW, no offense. BM spec=no skill.
Their shot rotation is based on macro.
/castsequence reset=3 Auto Shot, Steady Shot
/castrandom [target=pettarget,exists] Kill Command
Its just Autoshot>Steadyshot>AS>SS>AS>SS>AS>SS>AS>SS until the boss drops dead.
They seldom weave in arcane shots/multishot in it coz they are shooting too fast.
Weaving in arcane shots may even lower their dps due to clipping of shots and cooldown etc.
Honestly as a hunter myself, i think the Serpent switfness talent deserves a nerf.
+20% atk speed is too much. Maybe +15% is still reasonable.
I still prefer Surv spec though. Awesome AP/Crit and +AP buff to entire raid.
Oops. going wayyyy off topic.