Oivey...
I don't think I will ever understand clips like this.
Look, if you are just doing an instructional on a specific technique and such, yes I can see that you may not focus much on how to fight with it when you are showing how to develop power and speed and yes, your hands may be lower than they should and you may not be as tight as you should, etc, etc.
Maybe...
But when you are doing bag work or mitt work and throwing combos and using footwork then you MUST do it right, which means:
Hands up, chin down, head movement, balanced and correct footwork and throwing combos like they will be thrown in an actual fight.
Psalms 144:1
Praise be my Lord my Rock,
He trains my hands for war, my fingers for battle !