Not at all. He was demonstrating the kicks to teach the motions and mechanics throughout the kick. Slow speed kicks are actually Harder to do because you lose the advantage of momentum and dynamic balance. Also, there is no resistance so quite a lot changes. It takes more core and leg strength to do very slow kicks. You must also take into account the counter-affects of impact. The ball drill for example. Each consecutive kick was slightly different for the previous because he had to dynamically adjust for position. A great sparring drill since it simulates a moving target for power kicks. I agree with what andyjefferies said about the arm. That is a formal ITF thing that is done per style. Not wrong, not right so no judgement there. I imagine if you saw that gentleman sparring you would Not see that arm motion.