reply to Jame Ashby
If you ask any of the good old timers who have done knockouts in the boxing ring, they will show you the angle and direction of a strike and within the size of quarter where to hit. (even though PP's are the size of a clicker on a ball point pen.)
Back around 1982, we had a old timer boxer who retired to LBI. Kids would get in his face and push him around, until he clipped them and down to the floor they went while he drank his beer. At least three times each summer this would happen at the Hudson House, hole in the wall bar for locals.
I asked him how he did it, and he showed me two points on the jaw line with angle and direction to cause a knockout.
The angle/direction are very important, and make the difference. Even with boxing gloves or heavy clothes, it only changes slightly in using a deeper penetration, but the results are the same.
If you have a good trainer who has seen numerous knockouts, and understands angle and direction, you can find what they tell you in most pressure point manuals, accupoint charts, and striking charts for karate.
What you have to figure out is ... angle, and direction to use these striking points on the chart?
I could go on and on about the magic knockouts of different boxing matches and find the points hit with angle/direction on pressure point books, but then some people in this forum wouldn't understand it also relates to correctly using angle/ direction for Aikido techniques also? Let alone learning to intercept strikes correctly aimed at specific points when practicing Aikido.
There are many proven boxing strikes that relate to strikes in MA and Aikido.