There are a couple of standards documents which go a long way to answering many of these questions available on the CAA website. Any time I know somebody is coming up for test I try and ask them in advance to read Standards Document 19 - Guidance for Applicants for PPL Skill Test. It has chapter and verse and is not always widely known about. PPL instructors can also learn a lot from that and other documents (e.g. 14). There was one for examiners for the skill test too which told you what examiners should be looking for (and therefore, one could imply, instructors should be teaching) but I can't find that one just now. Well worth a read anyway.
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