Genghis,
Just want to add my voice to the list of people who thinks you don't actually need any instructor qualification to do what you're talking about doing.
A CRI can onl instruct people with a license, so would be no use to you. But an instructor qualification is only required if training towards the grant of a license or rating.
In general, there is nothing to stop you from allowing anyone else to handle the controls.... although if you're operating under an AOC, I don't know if that would still hold true. Surely the best thing would be to see if you can incorporate into your AOC some formal procedures for allowing your passengers to handle the controls? Then it would be very clear that it was allowed.
As for the comparison with martial arts, I've certainly wanted to inflict pain on one or two students.... but I've resisted the temptation so far!!!
FFF
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