Interesting video.....
Actually brought up one point that rarely gets brought up.......in fact i have never seen it got brought up in any youtube vid and i dont read any professional running websites so not sure if it's a thing.
It's the biomechanics and neuro aspect. Like for eg cadence, yeah it doesnt really matter but then again, if you are adept in doing 165-170++, then if you wanna try 3:15 to 3:55 pace range for say 1.5K to 3K distances (VO2 efforts) or maybe even 800m or 1k, the demands on your stride length would be WOW, well above 1.5 metres. Meaning both strength and explosiveness would be top notch and i do mean top notch
But of coz if you dont play middle distances or even 5k, then this is of little concern.
But then again, basically we can also put it this way, if for 300m and biomechanically/muscularly strength wise you feel that 3:45 pace is like totally feels wierd to you, then stuff like getting below 40 mins for 10k, the limiter is not aerobically already.