BOAC, sadly no longer do they teach the PRINCIPLES of navigation. Even if we never actually used Mercator Sailings in daily aviation, there was a reason why we were forced to master the theory. Some navies and coast guards share a similar attitude and no longer teach celestial to skippers and navigators. Such stuff is seen as unnecessary now that we have GPS even in our mobile phones.
It is interesting to watch how Gen X and Y can usually make the FMC sit up and beg, but when it behaves badly because of either finger trouble or a glitch they don't pick up errors that should be immediately obvious.
Good on the OP for his/her interest in the subject.