I'm not Ellis or Peter, but suffice it to say that the folks I know who practice Yagyu-ryu sword view the doctrinal presentation of many contemporary aikido shihant regarding "The Life-Giving Sword" as an "interesting" misreading that has more to do with the "harmony" = "love" reading of "ai" in "aikido" than it does Y. Munenori's treatise or the role the technical principle plays in the curriculum of Yagyu Shinkage Ryu.
Hi Fred! I only called out Peter and Ellis because they'd recently responded to this thread. It's great to hear from you.
So, the The Life-Giving Sword
connection to aikido is somewhat tenuous. My follow-up question: how commonly read was The Life-Giving Sword
in Japanese martial arts circles in the 20th century?