Tactical Surfing down a Staircase

When you think of tactical movements with guns, you would think of deliberate movements, covering all angle and cool postures.
Tactical movements down a staircase should be just that, however, these guys from Russian Systema Serbia may know something that we in the U.S. don’t.
These Russians are surfing down a stair case.
The first thing that comes up is how practical is this? And, why and when would you ever do this?
Other than to look cool.

Anyways its still fun to watch Not sure why tactical school is teaching this technique, but it’s definitely strange to say the least.
What do you all think?