Tic Tactics

A direct confrontation with an army much larger than yours is going to be a tough battle. Even Christina, one of the most cunning people in the game, was hard-pressed just keeping up with the stampede.

Just to be clear, two stuns that provide 100 damage each is much better than one stun that provides 300 damage. The more people there are, chances are, the more crowd control spells in a team, the better.

Not to say that great DPS is bad, but if the enemies have ample healing to back up to, they probably are going to survive much longer than what people expect. 

Sustain, block, damage, crowd control, buffs, and environmental advantages.

Those are what encompasses a group battle. In small skirmishes, what reigns supreme would obviously be damage. But in a fight of hundreds, no, thousands of people, damage's utility becomes less and less clear.