It was gratifying to make a new discovery, but as previously analyzed, its practical significance was limited. Replacing a powerful person's body with a clone came with tremendous losses, and the bigger problem was that the memories retained by the soul were far inferior to those stored in the cerebral cortex.
In other words, directly placing a soul into a new, complete clone to replace the original body would have an extremely severe side effect—serious, permanent memory loss.
If there had been a Memory-Memory Fruit user, perhaps such a problem could still have been remedied. But no one even knew where that Devil Fruit was now.
Thus, Mousse's original idea was more feasible after all. However, it could not be implemented for the time being until they found a world-class surgical expert, even though Mousse had made major improvements to it and greatly increased its safety.
"Does it really have to be brain death? If the heart stops, breathing ceases, and the soul is gone too, wouldn't that count as being thoroughly dead? Would that work?"
As soon as Mousse came up with this idea, he immediately conducted an experiment. The results proved that the "devil" was not actually that clever. It had fallen for the trick once again!
However, when Mousse tried to exploit the loophole further, he still suffered a shameful failure. Moving the operating room into his Book World did prevent the operation from running slightly too long and causing organs and tissues to die beyond recovery, but perhaps because time had stopped, the "devil" remained inside the dying-but-not-yet-dead body and simply refused to come out.
Having no other choice, Mousse could only have his ice-type Homies protect those organs and tissues that were difficult to restore through training. The safety of the procedure dropped considerably, and