On the basis that this was a VH registered aircraft and that the flight controls were fully functioning at the time of the event..
What about something constructive such as again teaching incipient spin recovery.
The idea of not teaching it and then saying spins are prohibited is great until a pilot inadvertently finds the aircraft in this situation without the skills to identify and safely recover.
Instruction by instructors who themselves have never experienced these sorts of manoeuvres provides a conduit to progressively lower flight standards and capabilities of successive generations of GA pilots.
Our regulator at work (NOT)