Of special interest, the article includes line length recommendations and techniques for using Zoom (multiple length) Tenkara Rods. https://www.discovertenkara.com/blog/tenkara-level-line-length
The attached article on choosing the most useful Tippet Length for the fishing conditions you are fishing under is also a different way of looking at things and equally excellent: https://www.discovertenkara.com/blog/tenkara-tippet-length/