Wow, they went through a real shitstorm..
I always have a knife (proper full tang 4" fixed blade knife, I hate folders) on me when I play, for utility purposes, I never thought of using it for "knife kills" and will never do..
Using (real) folding blades for gameplay purposes is just retarded, for some reason the blade unfolds and you actually stab the opponent -> easy charge for assault or attempted homicide (is that the right name?), other than sending the poor soul to the hospital..
Can't comment on TAG rounds, never seen one in action but my local shop has a few for sale, they're extremely light and my guess is that they don't really hurt if hit by one..
About KM, only recently started watching his vids (out of boredom, most of my favorite YT airsoft channels switched to other stuff or quit airsoft)..
Feels like he's a good shot, although some clips are rather sketchy..
That face shot is dumb, why tf would you hurt someone just because he's cheating (was he?) when you can call a ref and let him sort the situation out...