I just realized on my Hunter, if i run under the Dome while casting (aspect of fox) you dont get the Debuff which drains your life/slows you.
Mages/Shamans/Hunter and maybe other classes can use that to DPS the Shards from a safe position, you take no Damage.
Tested on Heroic.
Edit: You can even use a PVP insignia to remove your Debuff :P
regards