If they were on average in the middle, i'd say balanced. But that's not the case.
Being on the one fight that fits optimally the elemental aoe design and where you are expected to be top, just mediocre - well, that just doesn't work.
Elemental would be okay, if they were able to muldidot on the same level of shadows and balance. Then they would be able to keep up.
Mediocre for me is just the center third of all parses.
---------- Post added 2013-01-01 at 01:41 AM ----------
That's not true. On Windlord heroic, you also have to aoe adds until the end. On burst phases, you switch to pure single target and at the end of the fight (when you see that the next add wave doesn't die anymore or shortly before boss down).
So for 80% of the fight, AOE is very important on that fight and so is the cleave of chain lightning.