I'm not sure wether this is an exploit, or just a clever use of game mechanics.
It'll make the 4th Claw, on the DW encounter go down abiit easier.
Basically, what you need is:
1x Madness of Deathwing Encounter. & 1x Raid, with a Warlock in it.
Step 1)...
Form your raid - having one or more warlocks in it.
Step 2)...
Have all the warlocks in your raid, respec destruction.
Step 4)...
Clear all the way up to DW...
Step 5)...
Before engaging, have all your warlocks, to move to the platform for the 4th claw.
Step 6)...
Pull the boss.
Step 7)...
Have all your warlocks to Bane of Havoc the fourth claw.
Step...
Have them to jump back to the first platform.
Step 9)... Have them to complete the fight as they normally would, without using Bane of Havoc.
When i did this, on 10 man - singlelocking. I managed to burst just above 2million dmg on the Bane of havoc target(it having only been there for 5 minutes).
I had a decent dps on around 45k.
Now i havn't done this fight on 25 man, but i could figure the claws having alot more health... but then again, if you had 17 warlocks, all being destruction - you'd almost pwn the 4th claw without having to do very much!!!....
Enjoy!!....................