Content merged into JMA-Karate.
So why are they so silent? Too focused on their own way of study? Worried because everyone seems to have left it behind?
Also, not every person responds the same way, and besides that, you really cannot count on 100% success in hitting the spot.
Yet another answer is blunt force trauma.
The late Sherman Harrill with decades of work on the makiwara simply could strike the right point (anyplace on your body) and you'd go down. His school today is run by a senior student, John Kerker, and he maifests the same ability.
The secret instructor the makiwara and extensive studies of each kata movements application potential, then a lot of hands on striking.
The briefest of exmaple is found on my blog at http://isshin-concentration.blogspot.com/
They don't do kyusho or study pressure points, just strike.