This is something that, sadly, you'll need to discern for yourself Xana.
There's a
TON of political crap in the "Kyusho world" and it can really reek.
I know 'the truth' about where Dillman got his Kyusho knowledge from, and it wasn't "Videos"....not by a long stretch; and I'm NO lover of Mr. Dillman, though I also wish him no ill. Mr. Evan Pantazi, the head of KI, was a High ranking Black Belt under Dillman and did leave his org to begin KI....but Dillman was
not his only source of instruction and learning in the Kyusho/Dim Mak arts.
The points that I do agree with Sam on are:
1: You owe it to yourself to look up Oyata Sensei and or his group. Their Kyusho knowledge/skill is second to none in Karate. (Though I feel there are sources in the Gung-Fu world that go beyond their level, still...they don't advertise it and would be much harder to locate and get in with)
2: Kyushojitsu is not a stand alone art, it's the study of the vulnerabilities of the human body and how to access/activate them in order to gain the advantage in a conflict.....but it MUST be added too a fighting system or what I like to call "A delivery method". It is NOT a martial art but is an element that can be a multiplier to your arts effectiveness. IF nothing else, it's a few more things in your "Bag O' Tricks" to pull out and help you in a pinch.
In the end, my biggest advice, look to ANY and all sources that we've mentioned to study from....and then some. Don't pass up an seminar on the stuff, absorb whatever you can. Keep your ear to the ground, look up everything you can to help you learn more. Get books, get videos, clip articles.
Here's something else that may help you out as well. Since, for the time being, you are kind of going it alone, look to other sources of SIMILAR information. Study anatomy with a mind toward looking toward weaknesses and vulnerabilities. Look into "Chin-Na Gung-fu" which is actually a subdivision of most Gung-fu systems....it has a 'sub-study' in what it commonly calls 'cavity pressing' or Dian-xue / dim-mak. Look up books on Traditional Chinese Medicine (commonly refered too by "TCM")....because this is the body of knowledge that Kyushojitsu/Dim-Mak....etc; came from!! Study the points on the meridians and try to memorize their location, their number & name, their element and the direction of Qi flow. Here's a good sight for that study:
www.acuxo.com . They have Lots of info for you there on TCM.
DO YOUR BEST and enjoy!!!
But overall....don't give up.
The knowledge and skill is out there, now it's up to you to go and get it.
Your Brother
John