Below you can find a link to an article on Jigen-Ryu (“revealed reality school”). This was a system of swordsmanship that Sokon Matsumura is said to have gained his teaching license in and also taught to his students including Anko Asato (Funakoshi’s main karate teacher):
The following quote caught my attention:
“Jigen-ryu places importance on the first sword strike, which must be extraordinarily fast and powerful in order to defeat opponents. Jigen-ryu teachings state that a second strike is not even to be considered.”
There is a strong parallel to the karate idea of fully committing to every strike in order to end the fight there and then ("one blow- one kill") i.e. we don’t use strikes to set up other techniques or to weaken the enemy. The intention of every strike is to end it there and then; whether we use one strike or many.
Anyhow, I thought you may find the article interesting and thanks to Stuart Squire for the find.
All the best,