Handicrafting!
He recently learnt the truth.
Handicrafting rapidly raised the Sculpting skill. It also widened the number of skills affected by Handicrafting.
It boosted all manner of production skills with more gentle handling, such as picking herbs. It made sewing more elaborate and helped to restore the durability of repaired items. Even mages needed some level of Handicrafting. One could not hope to increase the Handicrafting by focusing on one skill and repeating the same thing over and over.