Everyone has felt blunt pain as well as sharp pain, these affect the exterior protective structures and can cause physical dysfunction. We experienced this, understand it and as Martial Artists we work to utilize it on our opponents.
This is however not the fullest of our capabilities with Kyusho... nor should it be the end goal. The true Kyusho practitioner must develop a greater potential to fully understand the skill as well as utilize it.
We need to pierce the surface to truly tap into the human essence, to illustrate this dynamic; think back to when you stuck your finger with a pin or needle by mistake and remember the feeling. It caused a reflexive action to escape as well as occupied your mind totally as you monitored that pain and reflex action. You may have spun your body around, writhed in other body contortions or even buckled at the knees adopting a more fetal like posture. Deeply embedded in your memory as all but the most dire trauma is (this folks, is the spiritual side of the Martial arts "Mind, Body and Spirit" expression), your mind returns to this trauma through out the rest of the day.
Now by contrast; remember the feeling of a syringe penetrating the surface layers as it sunk deeper into your muscle, right into your inner core, it was most likely revisited there in your mind as you saw this illustration above.
It was not the sharp pain and surprise of the accidental jab of a pin or needle, it felt more deeply invasive and wrong to your body as you felt it reach to your spine and up to the brain, some even get dizzy or nauseous over the intrusion. It also affected the breathing, blood pressure, heart rate, pupils and eyesight, physical strength, motor function and everything physical, emotional and yes even your spirit or will... this is far different and profound.
True Kyusho not only works on the physical plane of sensory and function, but also on the inner psyche of the individual... as in this description. To achieve this several components and body functions must be invaded together to achieve the depth of this example. Not only should the ability to induce this on another must be trained, one must develop the skill to be automatic and spontaneous in combative action and under adrenalized limitation.
Kyusho is not merely hitting a pressure point, (although at superficial levels it is), it is invading (conquering), the inner reaches of the opponents mind, body and spirit.
But does not need "Pin Point"method of accuracy to achieve.