You don't need to kill the adds in Satasha... Especially the last boss. It just slows the run down.
Overpower alone should be enough to kill the Satasha adds, so them focusing the boss should make the fight takes less time.
DPS generally don't kill mobs with low health in single target mode because the Tank AoE abilities generally take care of them before the last mob dies, so taking them out early is a waste of DPS unless the healer is really struggling or the Tank is running out of TP/MP.
