Very nice Demo
As to those who complained on not doing it faster or with resistence. Seeig this demp I was reminded of my teacher reharsing for a similar demo when I was starting to learn. He took one of his Advanced Aikido & Karate students (My teacher teaches both, and judo, for over 30 years) and worked with him on the show, They started workign faster and faster, my teacher did a technique on a kick, the student did not respond in time. I think they actually did the show in the end, but much, much slower.
The falls from kicks are nasty, and knee locks in those situations are even moe dangerous then on the ground.
Thus, this was a Great demo.
Demonstrations don't really let you know if the technique will work. They give you a false sense of effectiveness. Sensi Hiroshi Isoyama found this out when training with American Military officers. The American military officers were able to step over him simply resist in such a way that the technique didn't work. He had to make significant changes to make some techniques work or not use some techniques at all because they don't work on every person. All Aiki techniques don't work on every person. You must train freestyle with your opponents to test your techniques effectiveness. You must learn what really works and what doesn't in a full competition fight.
Demonstrations are just that, rehearsed sequence of movements. Free style, punches, kicks, locks, chokes and throws that you don't see coming or you do see, but require some immediate reaction is crucial to test a techniques real effectiveness. Yes sometimes a person will be hurt or injured. Perhaps wearing some protective gear if you have the fear factor will help decrease the risk of injury. Demonstrations isn't real fighting.