While I'm relatively new to the world of kitchen knives, in particular Japanese style kitchen knives with wa handles, I have looked at hundreds of these handles and I can't recall ever seeing a ferrule designed with a spacer and/or a change of material. I have seen some small tips such as Marko uses on some of his designs, but that's about it.
I was wondering if there was some sort of unwritten rule against this or if it a functional or aestheric issue. With all the amazing designs applied to the handles themselves, I find it very curious that the ferrule has remained, by and large,a single homogeneous piece.
Any insights into this would be greatly appreciated.