“What you wish you had learned in library school” can’t be taught, because it is totally dependent on three factors: what you learned before library school, what you learned in library school, and what job you managed to get after library school.
That sounds obvious, and it is. What isn’t obvious based on the popularity of this discussion is how radically different those three factors are among librarians and library school students.
If you were a business manager who went back to library school somewhere and ended up as an instruction librarian at a community college, your list would be totally different from the recent college graduate who went to library school and ended up as a reference librarian at a rural public library. Or vice versa.
The background, age, and experience of the student matters at least as much as the library school instruction. Learning What Can’t Be Taught « Annoyed Librarian