Healing

Availability
Like anything involving blood, Theurgic healing is expensive and available only to the rich and powerful. Some doctors claim to base their remedies on Theurgic insights into the proper balance of humors without actually using blood to alter that balance. That’s accessible to a slightly broader segment of society. And then you have apothecaries (again often claiming that their powders and elixirs are based on Theurgic alchemy) and herbalists, and at the lowest level, helot “ablers”. (source )

Proficiency
A Theurge who understands well enough how the skin heals itself could undo a scar by temporarily enhancing the healing telos of the skin. A less proficient one could heal wounds but leave a scar. A clumsy one who just wanted to increase the smoothness of the skin (something much easier to comprehend than the telos of healing) could temporarily remove a scar, but it would come back as soon as the blood ran out. (source )