You mean even after 3 years you were still learning how to add cream and sugar to coffee? Maybe someday in the next year or so I will ahve learned everything as you have appeared to have done since you became a journeyman. As you said, an apprentice does not know anything until he graduates.
And I did not say “I” installed the shutoff valves in the systems, I said they are already there for service purposes. Mainly to keep from getting scammed with a huge shutdown bill just to replace a valve or possibly a heating coil.