Have yet to get a group where the tank doesn't get insta-gibbed by the adds. Neither when I was healing, or when I was DPSing.
Maybe it's just bad tanks.
Also: I am now deciding to venture into addons, even though I was really hoping to just use LUI again (since they moved to Wildstar!)... but they don't seem to be ready yet.
Figure I'll just use some simple ones for now.