Please note, I am not the "first without sin", Just remember this accident and the fact that, as Yenn says,"Over the years I have seen many instructors and many of them are forgotten as they were poor."
The Board of Inquiry concluded that the instructor devised a demonstration of asymmetric flight that was 'inherently dangerous and that was certain to lead to a sudden departure from controlled flight' and that he did not appreciate this.
https://aviation-safety.net/database/record.php?id=19911029-0
I'm not wishing to be controversial, a stirrer or indifferent to the suffering of families or others. Just saying. Don