Sorry, but that is exactly how the apprenticeship program works in most
of the skilled building trades.
I've been around heavy construction all of my life, and I know hundreds
of people in civil/infrastructure work and unless they are an engineer,
or some other professional, they learned their trade by working their
way up, I know of not one single person who went into an apprenticeship
program to do such.
Which has nothing to do with my outline of how union apprenticeship
programs work.