Maybe he was demonstrating that it was not possible and they pushed it too far.

On the other hand I have managed to turn around at 500' with a strong headwind in a C152. I have also seen a Pawne almost making it, but hit the tip on the runway and ended up killing himself. Had he not gone for the concrete but just for the property it would have been survivable, much better than the rooftops. I have even had a DE telling me to just do a half lazy eight. I was scratching my head after hearing that one.

I doubt the majority is teaching the impossible turn. It is for the rare occasion when conditions are just right. It is not privates, especially not for doctors, or lawyers. (joke)