Virtual hp is the only way, you know if Blizzard doesnt make SC2 eventually, maybe in a few years us mapmakers should start making it, lol. Wishful thinking, but it would be nice to do with maps the posibilities we know are there.
I dont even care if sc2 comes out at this point, I've stopped hoping, but it would be nice to have a mod that allows us to make really killer maps, we are so limited in what we can do, because of the lack of options and detection of things.