>I suspect at the basecode level, it's really just about pushing chi
>around. Heck, there's probably even a way to do it with fire,
>although I would assume that would be very tricky. Like basing a
>health potion on hydrochloric acid. :)

All life is flame. What a firebender healer is doing is giving the cells in the body more flame so they can repair damage faster. This contrasts with, for instance, an earthbender healer, who focuses on giving them a scaffold to grow on.

I suspect a full circle of healers from all four elements could even bring back someone who was, as the experts say, "mostly dead".