Comment by simonask

The problem is that understanding everything from first principles is often the longest and least efficient road to learning the things that are actually useful.

Psychoacoustics is interesting, but it's not something that really helps you become a better musician for at least a couple of _decades_ of your journey. For the vast majority of students, it's a complete waste of time.

It's extremely unlikely that you learnt algebra or calculus from first principles, either. You started from the other end, learning the tools and skills to put it to good use, and then dove deeper with those tools already under your belt. Musicianship is no different.