The few times I've done him, I haven't worn any NR. Typically we have a hunter with us, so he just keeps aspect up and we have a shaman in the other group use a totem. We bring 3 healers, and just completely ignore the birds. Last night was the only time we had an issue with him, we got him to 20% but we had no hunter and 4 melee dps(normally we only have 1-2 melee dps). The first time I tanked him, I had about 15.4k armor, 14.6k hp unbuffed. As long as you aren't melee heavy it's typically people not properly collapsing during the storms, and then spreading out after that has wiped us. Once the group gets that down, he goes down pretty easily.