“Hey, Jack would succeed if he tried to cut Bonesaw. What if Jack weren’t controlled by Jack at the time?”
This does not apply exclusively to Jack, by the way. Bonesaw claimed that Jack would be able to do this because he had the same safeguards, suggesting that anyone with the same safeguards could do it, and probably some of if not all the members of the Nine for whom the safeguards don’t apply, too. Presumably she didn’t want to protect the Nine from the other Nine.
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