I recently heard about such a 'demo' exercised by a very(!) experienced EC pilot many years ago in a BO105. Motto: Let me show you how this works.
Demo started with a clearance at 13.000' near Ottobrunn and ended .... at 2.800' ... the two POB did only survive because they both leaned forward as the aircraft had a complete loss of control ... pitch was through the floor (literally) and PF was definately not PIC anymore.
From my point of view for some things in life it is absolutely ok to know what can happen, to realise the beginning stage and the action you have to take not to really get into trouble.