Thanks for posting, that was interesting.
But I prefer a twist shifter that I can get more of a grip on and I do not see wood accomplishing that. In late 2016 I moved my shifter to the right bar end on my Nomad Mk II with drop bars using the Hubbub Adapter. I have the second generation round shifter, bought it in early 2013.
I have posted here what I did several times. The rubber abraded too easily, was wearing down. There is a product in USA called Shoe Goo, I do not know if it is sold in other countries. It is a viscous liquid, comes in a tube like a toothpaste tube. You can apply that to worn shoe soles to build them up as they wear down. The liquid has a lot of volatile chemicals in it, I do it outside to avoid breathing them, it shrinks as it hardens into a hard rubber like substance. It comes in clear or black. I used the black, put on three bumps, two layers, similar to the old triangular shaped grip.
First photo is from 2016 soon after I put it on, at that time the shifter was three years old. Second photo is from January 2022 (winter, snow in background). Shoe Goo is holding up really well, almost no wear on it and it reduces the wear on the original round shifter rubber.
I tried many other things prior to the Shoe Goo, but all eventually did not perform well but the Shoe Goo is a keeper.
I might eventually buy a new shifter, but not in any hurry to do so.