Thanks for the grip training link. That is very useful. Yes, many people underestimate the grip strength required for holding a knife. Doing full on strikes with a training knife on a heavy bag will give most people a much more appreciation for it.
One big advantage that I like about Pikal is that it utilizes a locked wrist and convulsive grip. This removes the fine motor skills required for the draw and also makes for a more stable grip with less chance of accidentally losing the knife.
BTW, what system does your brother practice?
balancing dragon, a system of his own devise. I don't feel that i'm in any place to explain any of his systems in detail, because I don't have the extensive background he does or the technical mindset. "balancing dragon" contains weapons systems, grappling, and bare hands. the weapons system is broken down into katana, screwdriver/spike, stick, and knife systems. each system has separate parts for single weapon and dual weapon use. the katana has forward and reverse grips, the screwdriver system is interchangeable with any weapon that is pointed and long enough to hit the brain, the stick system has a specialized portion dedicated to crowbar use and is interchangeable with machete's, and the knife system has separate parts for different types of knives: folder, short fixed blade (3" or smaller) and medium fixed blade (3"-7"). the idea being that you shouldn't stab with a folder, and you can't hit the brain lungs or heart with a 3" fixed, so the most effective fight stopping techniques will change between blade types.
and there are also some small sections dedicated to individual ideas and applications, like how to move a persons body weight effectively during shoves and pushing.
for the most part, the underlying idea for his work is that you will be smaller and weaker then your apponent, and possibly out numbered. so your techniques shouldn't rely on overpowering your opponent (because he will always be stronger then you), and you should be ending the fight as quickly as possible.
I like his core systems because they are direct, and are logical in their approach. sparing with him makes me feel like i'm 5 years old again. everything I do opens me up to something horrible. the only thing i've got on him is boxing, and i'm quite positive that he could close on me and leave me with nothing.
knife sparing with him is an non stop teeth clenching hair raising squirm fest. to test me the first time i did an actual spar with him, he used a fast slash pattern without crossing his arms (if you watch a guys slashing pattern and can catch him crossing arms, you can potentially push in and temporarily block both arms against his body, opening him up for one good head shot), so it felt like there was nothing I could do to step into him, and all I could do was get my forearms cut up.
*shudders*
mostly I just keep dreaming of my iron claw system. a system that only brad johnson could use

vulcan neck pinch? oh it's real alright. brad johnson can one arm
pinch grip pull up off a 2x4 while pinch gripping a 10lb weight in the other hand. he grabs your neck, that muscle will no longer be attached to bone.