I was just getting my ass handed to me by the phase spider matriarch, but thanks to "Help" it stood no chance. It kept killing my weakling mage, which Shadowheart kept helping back up, while Lae'Zel and Astarion kept hacking away at her. I should be dead many MANY times over, but because Help is actually a miniature Cure Wounds, I suspect any fight that involves a single opponent will forever be cheesable with Help.
If someone is dying, Help should be a medicine check DC(10) to stabilize so death saves aren't rolled anymore, and then after the fight the stabilized person can get his 1 HP to stand back up.