Had insights again.
It's related with fighting with tense muscles or other body parts, therefore with an article about Re-Training Crotch & Groin Kicks as well.
When i get hit in muscles or other parts, it's natural reaction to back off, to turn defensive. after hitting once, skillful martial artists have tendency to hasten attacks, to barrage with strikes. it's also called a 'Attack Tempo Increase'.
It's related with 'Long Fights' duelling strategy as well.
When i'll be prepared to fight with tense muscles or other body parts, i can strike with stiff leg or other body part quickly - often suprising unprepared opponent, 'turning tempo against him'. Then i can increase attacks as he or she defends, forcing him or her to defensive.
It's a strong defense/aggression maneuver.
i think it can be lifesaver in many real combat situations, including when armed with weapons.