a luthier master, called "Sensei", is overseeing all steps of the construction.
So there are workers and a superior foreman/floor manager with some higher responsibility? Yeah that's completely unheard of in any industry.
Wikipedia says that "Sensei"
is a honorific term translated as "person born before another" or "one who comes before". In general usage, it is used, with proper form, after a person's name and means "teacher"; the word is also used as a title to refer to or address other professionals or persons of authority, such as clergy, accountants, lawyers, physicians and politicians  or to show respect to someone who has achieved a certain level of mastery in an art form or some other skill, e.g., accomplished novelists, musicians, artists and martial artists."
So that may appear remarkable to people who only heard that term in some 80s teen movies and call their superior "that stupid a..hole Mike" but maybe that's just regular formal work conduct, if not just made up. Another thing that's quite common is people taking any opportunity to upvalue their guitar's brand image in preparation of selling their stuff on eBay or defending their buying decisions, and failing at it. Creating a rather contradicting image of a "Sensei" slowly walking through rows of workbenches, sternly monitoring every stroke of work the "best luthiers" do (and not contenders for an internship or something) seems a bit overdone. Also he totally forgot to mention that anything hardware is made by a master swordsmith.