This particular test is unique to the Bujinkan. The other related arts reportedly have similar testing, and you can find various opinion so of the reality and relevance. In the Bujinkan, as I understand it, Hatsumi is the sole arbiter of pass or fail. Though he has allowed a very few others to swing the shindig on occasion. I've watched several video of the test, and in them, I've seen him fail people who evaded it for, I suppose, the wrong reasons. I've seen him pass people who reacted, but didn't completely avoid the sword, too. Based on that, I have to assume there is a particular quality or character to the reaction that he watches for, rather than simply picking up on timing or sounds.
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