We all the time have something to learn, even the the GC!

I think of the GC having his five master skills as like an honorary degree. I don't think I'd want to trust any work he did any more than the work of any other five-year-old.

As a famous genius has said: "the only thing I know is that I do not know any thing"
I mean, even the GC with all his skills may go to school!

I haven't seen him search out anybody who's sick like the doctors do. But I did put him on a guy who was sick and he healed him.

he won't search people out to heal them, and any villager can heal when you drop them on someone

his big "help" with healing is that if a villager is sick (or the whole village is sick, as happens sometimes) and the GC throws a party, everyone who goes is instantly healed

he did have a party for me once and a farmer who didn't like crowds or dancing continued working and did not attend the party, when i checked him he was still sick

i am not sure if it was a fluck or because he did not attend the party, so