I believe there is a place for pressure point usage. Especially in the grappling/clinch range. In fact Evan Pantazzi has a great tape on pressure point grappling. It is one of the best in my library.
But to think you can use Kyusho to knock some one out it in a real adrenaline filled physical engagement is unrealistic. If ever attacked on the street are you really going to try to find a quarter size point on some 275 pound dude's gall bladder meridian and try to knock that person out. The motor skills required are too fine; not to mention there just would not be enough time.
Gross motor skills and blunt trauma are where it is at.
Dillman and Pantazzi knockout videos are fine exhibits of parlor tricks, but that is where they should stay. In the parlor.
Stanley Neptune