Really well made. I actually see a lot of work and reference into these although they don't apply in every scenario it gets a good grasp of the basics.
I would have tough there would have been the stance where you go full defence of the vital parts. Or (sensible parts) were you cross your legs to whit the help of the arms cover the entire vital spots of the body.(Legs for lower body and arms for the stomach to neck) Sadly I don't remember what its called...
Still this is a good tutorial. If someone is reading this don't go and fight. Follow it and get away. If you got no choice then its possible to use depending on situation, just don't forget psychological aspect and the environment. Seriously throwing stuff or other things can be more efficient then actually engaging, even if its only for distraction. Also we can just attack the feet's by advancing. like step behind the leg or something in hand to hand to get closer and strike in the stomach. Balance is the rock for every stance and move, lose it and you fall helpless in most cases. (Just to say the stances aren't perfect, but its more or less closer to instinct on what is showed)
Basically just don't do stupid things and don't get over confident for knowing the basics. Its good ,but a simple mistake could be fatal... Fear just makes us more prone to it. And knives if you just want to pin im down just take is arm, make it curve to the side. ( Important part if he attacks right use left to curve if left use right to curve it) So you can grab the hand, get behind is back and press (forward motion to push im down like a lever) on the shoulder to pin im down. Ends up whit is wielding arm locked on two spots to block movements and you actually go on im to prevent im from getting back up. Success increase if you place your foot in front of the one whit the side your pushing. Rest will depend of its physical strength and your weight, etc.
Ps: 1)one thing I didn't see in this. You disarm opponent but it doesn't specifies you need to make sure keep im ''down'' You get it, good job! Now make sure you keep the weapon out of is hands and do not think your the only one who could disarm and he might still want a fight.
2)Gun defense, my tip is wait till there are no bullets if possible. Ammo depends, but if its auto the average is 2 sec of continuous shooting for normal guns. Also whit little luck he's to stupid to get enough ammo and might not even wield a knife. (still cautions is advised) Analyze and react to the best of capacity's.