Methinks the sticky point in this discussion isnt as much about what the character can actually do when he's ready to sacrifice the character, its what would an opponent reasonably think said wizard could do with it, since fear of the DeathCurse is one of the prime protections a council Wizard has. Once the dramatic moment comes it can be left up to the Awesomeness of the moment; but before the character is committed to the sacrifice, the Curse's power is still relevant in terms of motivation's and tactical planning.