This bunkai sequence drill for Kata Fukyugata Ich teaches students the significance of preemptively striking the enemy when escape is impossible and deescalation has failed. A key combative principle is that when defending oneself with violence, one must take the attack to the enemy instead of remaining in a purely reactive posture.
The drill teaches a second key principle: the offensive attack may not work, and the enemy may counterstrike. The kata shows a variety of responses to possible counterstrikes. The drill always begin with and returns to the opening sequence–the preemptive strike. The other portions of the kata demonstrate how to deal with various possible counter moves and responses from the enemy.
The video is longer than normal, but if watched in its entirety, these concepts and principles should become clear.