My guild is currently on Kael'Thas but the biggest problem for our members is picking up the weapons after they go down in phase 2. Is it possible to make a macro that will loot one of the weapons after it dies?
There is no macro that will activate itself to do anything.
That aside, I am pretty sure there is not macro command to loot a body.
Either way, you still have to click to loot. You might as well just loot the body.
we're working on kael as well and last time we tried to have each weapon's tank pull the weapon a bit out of the group just before it died which helped.
The key for us was to separate the weapons just before they died. We would normally kill the staff first off to the side, then AoE starts. As each weapon was about to die, it was dragged well out of the aoe. If that didn't work, we moved the aoe pile.
A second thing that some folks used was to create a targeting macro. It cannot loot for you, but targeting the dead weapon can give you an idea exactly where to click.
Lastly, I always found it helpful to have auto looting on for this encounter. Saved me a second or two picking up each item...which doesn't hurt.