Man tells his apprentice, put mortar here, here and here, then slap on the brick and tap gently to level. For the next 20 years, that's all the apprentice does, exactly what was shown. He can lay bricks fast and well and level with perfection. Doesn't make him smart or an expert.
Understanding Why the mortar needs to be in certain places, How much mortar, the Consistency of the mortar, Reasons for using one mortar over another, Understanding temperature variations and affects, Differences in bricks or blocks and mortar requirements, That's what would make him smart.
It's one thing to build a pc, it's nothing really more difficult than playing with Lego's. Understanding How, When, Why, What makes up a pc, the relationships and composition of the equipment, quality, and other factors used in building the pc is a whole different ballgame.