As far as I can tell, aggro functions quite normally in that raid. Whoever has most hate has the aggro, unless he's far away and someone is right next to the mob. In this case the mob aggroes on the close standing guy.
Hey now, even if my gear's broken, my movement speed's gimped to the point I can't avoid dragons' fireballs, my monk abilities disabled and I die from one hit does not mean I get to stop doing what I've been assigned to do in the raid. :P