Is it true that a plastic surgeon knows how to remove a mole while reducing the chances of scarring better than a dermatologist? how so?

So so: Plastic surgeons are specialist trained in surgery. That is not to say that a dermatologist can't remove a lesion without the same results.

Depends...: Many dermatologists do excellent mole removal, with the same care that a plastic surgeon would use. But some derms don't really enjoy doing surgery, and in that case, you would be better off in the hands of a plastic surgeon.