But this is something they will encounter on their own if they pass their test. Better to improve their observational driving skills, rather than pass because of prior knowledge.
They will improve soon as they pass their test. Out on the road solo. I can't see any reason not to give a learner the best in depth training before taking a test.
Think of it like mock exams. Didn't you learn exam tactics/ keeping calm from those mocks tests?.
Just like learning to drive, practice run first.