It's not like he's actually training for a fight or anything. It's for guys to do at home with little equipment. No he's not always using proper technique, he's showing the process. I'm sure he knows how to do a proper push, pull up etc. He was in special forces.
If he were just starting in this day and age, with all the advanced in everything over his time... He would be a beast. Those high kicks are legend. So fast and powerful. He was the real deal, deserves respect from anyone who claims to love fighting.