The drawing of magic circles and carving of runes was a very technical job, and it was this world's unique product. It wasn't like a pure 'drawing' like everyone imagined. It was indeed as simple as drawing according to the blueprint, but in order to become a Runemaster, one couldn't just learn to draw.
If drawing magic circles were as easy as following the blueprints, an ordinary person would be able to do it. Even a commoner who couldn't sense magic could draw the magic circles as long as they were instructed on how to draw and what to use when drawing. It would become a simple 'produce-then-repeat' job.
