Therapy (& psychology)
This concerns accompanying drivers as much as learners.
When with your learner, mention only things that are relevant and on-topic. Be constructive and supportive, to help "their journey". Timing matters. And exact words. Plus your pace and tone. Body language, too. Try to avoid fidgeting or making notes. Keep calm (by using e.g. the sun-visor mirror to know what's behind). Sit well back (to watch the student, as well as everyone else). Reflect verbally with them on their experience. Don't make them see it all through your eyes. See it through theirs.
On test, a driver will usually read all sorts of past experience into the person assessing them. (It's called "transference"). If you find their "vibe" puts you off, try a test centre where examiners don't remind you of anyone.
Any therapy has the aim of enabling the participant better address future challenges, staying positive about "being out there". And it makes sense to avoid people or situations that undermine our confidence or performance. Just like learning to drive in a safe environment, then doing it on your own in places and with people you feel comfortable.