Alright so from what I've been reading the general best strat is to have a warrior tank stack the very most block value gear that is available and tank all four adds, heres the main post i've been reading on the EU wow forums and generally a very viable strat.

NOTE: THIS STRAT WAS PRE 3.2.2 AND IS ONLY VIABLE USING TWO BLOCK SET TANKS INSTEAD OF JUST ONE. edit: nevermind, its still somewhat viable

http://forums.wow-europe.com/thread.html?topicId=10920982122&sid=1

"Yeah, at least for any guild that downed the twins.
Fast answer : get a warrior to tank the 4 Nerubian Burrowers (maybe a paladin can do it too).

Long and argumented explanation :
What are the difficulties of the anub'arak 25 hm encounter ?
In p1 tank 4 Nerubian Burrowers that buff every other burrower in a 12 yard radius http://www.wowhead.com/?spell=66129 and stack a debuff on the tank http://www.wowhead.com/?spell=67847
In p2 kite the Pursuing Spikes http://www.wowhead.com/?spell=65922 (did any guild managed to do it without at least one Hand of Protection per phase 2 ?)
In p3 same as p1
+ heal 5 random raid members which will take a 6k dmg per tick dot for 18s
+ beware of any member that as not a sufficient selfheal to overcome the minimum 250dps boss aura http://www.wowhead.com/?spell=67630 (in HM it is 30% per tick, not 10%)
+ heal each tank for at least 12k hps more because of this Leeching Swarm
+ kill the boss before the enrage timer

Of thoses difficulties, the biggest one is to tank the 4 Nerubian Burrowers.
Let me explain :
Each burrower has 728k hp and hits every 1.5s or so for ~3k a tank, when they are alone. (~2000 dps without avoidance)
They stack a +30% physical damage debuff on the tank, so, the more he has burrowers, the more he will have the full +300% damage.
Each burrower attacks 100% faster for every other burrower within 12 yard.
So if you take 1 tank for 2 burrowers, he will take 3000 * 4(+300% from stacks) * 2(# of burrowers) * 2(attack speed buff) when the debuff is stacked at 10.
Tanking 2 burrowers results in a 20 to 25s period with 10 stacks every 45-50s. The tank must mitigate 32k dps. If he has 60% avoidance, it's a good 12-13k dps, with a lot of spikes.

The p3 main difficulty is to dps those Nerubian Burrowers while dpsing the boss for a lot more than what it heals himself for.
The boss generally heals himself for 75k hps. Because of the enrage timer, you have to dps it for at least 110k dps. You have 3 tanks to heal, and 5 random players in the raid who will take a dot. So top guilds generally bring 7 healers and 3 tanks. Conclusion : You have to sustain 110k dps on the boss with only 15 dd (7400 per dd), while also dpsing 4 burrowers with 728k hp every 45-50s.

Because we have to maintain a very high dps on anub, the 4 burrowers must be very close to it. So with 2 tanks on the burrowers, we have a configuration like on the Paragon movie : 2 spots with 2 burrowers very close to the boss, but at least more than 12 yards from the 2 burrowers of the other tank. But not to far, because of the range of the ae (fok/wipe/cleave/ww etc.. 16-20 yard diameter on average).
This requires really precise positionning of the 2 tanks, to make the ae optimal and avoid a second Spider Frenzy buff on any burrower, or he will take a lot more damage. Once the tanks get the trick, your problem will be to meet the boss dps requirement while dpsing those adds. You now have the explanation for the 4 rogues, 2-3 dk's and 3 mages we see in a lot of the top guilds damage meters.

Bring only one warrior to tanks the 4 adds.
Hey ? Am i crazy ? He will take at least 70k dps with spikes at more than 150k dps ! How is it even possible ?
Really Simple : Stuff him with every single item in the game that has block rating and block value on it, while also having dodge/parry/def not to gimped.
The burrowers hits a tank for 3k, it is the tank debuff that make it jump to 12k. If you block it for 1500, he will take 1500*4 = 6000, not 12000-1500 = 10500.
If you have a warrior with a sum of miss/parry/dodge/block >= 100% with a block value > 3k, he will takes... no damage. Yeah, it's possible, premonition did it, and you can check it on their vids and reports : http://www.worldoflogs.co...Taken/?s=6337&e=6598 is the report of the third p1 + p3. Xav only takes 320740 melee damage in 261s, that's only 1230dps... with 4 adds which hit him more than 10 times per second, any tank without block would be instantly gibbed.

What are the advantages of this technique ?
- You don't have to wipe because your 2 burrowers's tank don't have the perfect position and the burrowers buffed themselves too much.
- No AE range problem at all, the 4 adds are exactly where we want them to be (very close or under the boss).
- 1 more dps to bring, and maybe 1 heal less.
- 1 tank less that heals the boss for at least 12k hps

The only downside of this technique, is the redirections to do on 3 of the 4 burrowers to make sure they don't hit anyone in the raid when they spawn. 2 hunters and 1 rogue can do this easily.

Sum of those advantages : less wipes because of burrower's tank death, and the equivalence of at least 3 dps more only on the boss, trivialising the dps requirement. You don't have to bring 4 rogues anymore (which is exactly premonition's case), you can bring any dd, with of course a minimum AE dps.

Any good guilds that downed the twins can down Anub'arak with this technique, because the 2 biggest difficulties of the fight are totaly avoided : burrowers tanking and positionning, and boss dps requirement. "

Yeah I agree with dank, we should always use the West ice patch on the first call, then the east the second time, that should make things very consistant and help that part out.

Edit to change directions