I was curious about this unit as well. As a side question, has anyone compiled a list of all the unit and hero types so we are able to compare them? I mean I am sure there is some data on the wiki's, but would be nice to see like a huge chart comparing all the races.
But as far as your first statement, yeah everyone gets their HERO unit that can do the mass heal, but having another unit that can do this is pretty handy. As far as I have seen, you Hero is the only unit that can do this. Granted some can heal themselves, but healing others can be pretty handy. I am debating about picking one of these guys up tonight after work and taking him for a test run.