Let me attempt to clarify. The role of our muscles tendons and ligaments is to support or postural alignment and recover our body for the next support. Staying on the ground longer than necessary creates greater effort to go a given speed. Since there are multiple forces involved it takes a specific coordination of the body to insure that the forces are working in harmony with one another. The end result we use the least amount of our energy and effort to allow our bodies to move/run. Better??
Not much, sorry.....maybe I'm a bit thick today. If I'm moving very slowly (as in your video above) using the least amount of energy may in fact have been walking. It seems to me it takes quite a bit of effort to keep my feet off of the ground when I'm moving very slowly. When I'm moving forward at a reasonable clip it becomes easier because I have more inertia, and I'm not just moving up and down (which is wasted energy). Jogging in place is wasted energy. Jogging very slowly is less efficient than walking. There is a point (speed) where breaking into a run is more efficient, and then the question is what is the appropriate cadence to be most efficient and avoid over striding, etc.
Lee's comment that your cadence was too high for the speed you were running was simply a subjective judegement on how you were moving at that particular pace.
Thanks for attempting to clarify though.