The only unit with single unit healing capability are the shamans correct me if I'm wrong (and I haven't played for three days), and they automatically heal units unless otherwise commanded (?). The rest are dragon skills that heals AoE. IMO micromanaging for health is not effective as compared w/ the medic for Starcraft.
That's a good point, but I was thinking of telling a wounded unit to pull back, not telling a unit to heal the wounded one.
I haven't tried it out. If that can happen, they should remove that feature.
Yes, it happens all the time.