Simpson "Tomahawk" Training sticks, 1960s

I'd seen pictures of these on the internet in my research, and when I had a chance to buy a pair, I jumped on it. The sticks and their system of rubber balancing rings were designed in 1962 by Allan Simpson Jr. and awarded a patent two years later. Without the rubber rings, there's really not anything remarkable about the sticks; even the carved "notches" have been seen on other drumsticks.
But Simpson designed his notches to take a set or adjustable rubber rings. Move the rings forward and back along the stick, into the notches provided, and you could ostensibly change the balance and feel of the stick. As you can see in the photos below, these are designed to be used with traditional grip only, which would have been the preferred grip in Simpson's time.


Below is the illustration of the system from Simpson's patent application:

The sticks I purchased were New-Old-Stock from a music store that had been bought out some years ago. My sticks arrived without any packaging or instructions. Online research hasn't turned up any photos of someone actually using these sticks, so I had to read the patent application to know which stick is meant for which hand.

 The sticks measure 17" long and are around the same diameter as a pair of 2S marching sticks. The wood is lighter, and the tips considerably bigger than most modern rudimental sticks.
 Playing on a rubber pad caused no problems, though if you want to really slam it out these are not the sticks for you. They definitely have a lighter touch because of their lighter weight. They also make the unfortunate model name ("Tomahawk") seem a little incongruous.

Right hand position:

Left hand position:

There is a web URL for Tomahawk Training sticks, however, the link is not functional. I've found no other information on the manufacturer or on any other designs Simpson may have patented. I also don't know how long this stick was available. I've seen other Tomahawk sticks for sale on the web but don't know how many were actually made. It's a mystery, and an interesting one at that.
Fellow drum geeks are welcome to share additional info with me.