No video will show the subtle differences. The principle is that you would let the physical aspects of the ride flow through your bike to minimise shock and allow the bike to more naturally ‘fall’ through the path that will take it the easiest.

An good analogue would be jet skiing. If you just hold on for dear life and hope for the best, you will get a very sore back. A lot about doing it right is letting the waves do what they have to do, and making subtle corrections to ensure your path is optimal but taking into account the obstacles it’s encountering

Are they talking about hiking or biking?

Walking is basically controlled falling. This is basically an extension of that. You just let one leg go in front of the other like you were walking, rather than taking singular steps.