Predictive argument for multiplicity

Multiplicity is the name (among other names) for the concept that the science of superimmortality uses for the fact that that two or more bodies can produce the same ixperiencitness at the same time. The structure and functioning, behaviors, and consciousnesses produced by the different bodies do not have to be the identical to produce identical ixperiencitnesses. Your consciousness was different in the past and will be different in the future nonetheless you experienced these different consciousnesses. The structure and functioning of your body but specifically the structure and functioning of your brain produces your consciousness and your ixperiencitness.

We can compare the predictive power of the concept of multiplicity with two other theories. The first theory is supernaturally based on the concept of a soul. The other theory is based on the body alone. As of now, as far as I can see, neither theory uses the concept of ixperiencitness so both are at a disadvantage when they are trying to develop a theory that predicts when a body produces "you" when you are any designated conscious being. The first theory is vague when defining how the soul is connected to a body to produce you. The problem is there is no soul to scientifically study, thus there is only speculation about its existence and behavioral interaction with the material world of bodies. The problem with the body theory is the belief that after death there is no conscious existence again for a conscious being. But what is the definition of death? With the concept of ixperiencitness, scientists can ask under what circumstances will a body produce a specific ixperiencitness and when will it not produce a specific ixperiencitness? The body theory usually believes that after death of a body the ixperiencitness that a body produced can never be produced again. This is a simple clear prediction usually stated as "After your death you will never experience conscious existence again". Why then is superimmortality's multiplicity a more predictive theory?