User blog comment:Baptain/Second Fruit Theory/@comment-24769684-20160809014159

All we know right now is that Kaido is seemingly immune to physical trauma, not that he can't do stuff like drown or die from Devil Fruit consumption. I'm still unconvinced that he's actually trying to kill himself, only trying to push his limits.

Even if Mansherry's healing could apply, I doubt the eater's body would simply be able to handle two Devil Fruits after being healed once, rather than just destructing all over again.

And Brook still has the Revive-Revive Fruit in his second life, despite the fact that it carried out its main purpose it is still very much a part of him as seen in his soul-related abilities post timeskip.