Hey Aaron,
Well unfortunately there are a number of kenpo "camps" that have nothing in common except perhaps for the name kenpo. A couple of years after Mr. Parkers death Mr. Mills, to make a long story short, left the IKKA to form the AKKI. He has since revised, altered, and created the curriculum that the AKKI uses today. Along with this, he and the board have introduced the AKKI Universal weapons system.
The weapons that this system focuses on are the knife and the club. Each weapon has 3 levels of proficiency, however at this time the second and third levels are in the process of being completed. This is not to say that material from these levels is not being taught, rather Mr. Mills just hasn't decided to formalize it yet. You know how people get when you print things in a manual. It suddenly becomes the unchanging gospel, whether it's the best way to do something or not.
The knife work, while incredibly similiar to some of the empty hand material, requires some advanced training in order to maximize it's effectiveness without being a danger to yourself.
I have seen many people who, with a weapon, proved to be more dangerous to themselves than any would-be attacker.
The good thing about a Universal Weapons System, is that the stick work uses a number of the same principles found in both the empty hand and knife material, but due to the weapon's physical form and mass, an advanced understanding of the weapon is necessary and thus advanced training is also required.
Neither of the two weapons are taught at specified belt levels, rather the respective curriculums are introduced to the student, usually, no sooner than orange. By starting so soon, this gives the student a chance to develop corresponding skills as they move through the art. I have honestly found that principles taught in the knife and club curriculums have helped me understand and develop my body mechanics, stances, and hand coordination in a way that I had been overlooking in my empty hand material.
Both curriculums are outstanding, sometimes quite gruesome, extremely effective, and completely kenpo based. While there are some similiarities to arts like Kali and Arnis, trying to compare the two would be like comparing wrestling to BJJ. Sure there are similiar principles and movemets involved but they are obviously seperate entities, each with their own strengths.
I can only try and describe what is happening from the AKKI perspective, I'm not completely sure what the status of weapons training is in other associations. For information on other Assoc.'s, you would need to ask their students.
I hope this was at least informative.