When you make up a doctrine without consideration of the whole context then you often create new problems.
If your spirit is merely a life force like electricity, then when you die there is no part of you that survives death. You simply no longer exist. That is okay, as atheists and materialists that have no spiritual beliefs think this way. The problem comes when a copy is made of your body and those stored memories are implanted in that copy. Since you ceased your existence, it would not be you as there is nothing to carry the continuity of your being. It could be a perfect copy right down to the cellular level, complete with replicated synapses and memory, to the point that it thought it was you because of having your memories, but it would not be you.
It would be just like making a backup of your PC and then running the PC through a grinder, then copying the data to a new PC. You can run all your stuff just like it was before, but it is not the same PC.
This has other implications. Once you are on to the fact that you will be blotted out of existence forever, you might decide to live for this life. After all, it won't be you getting resurrected. If your duplicate in the next life gets punished for your misdeeds, or not resurrected, well too bad. It's not your problem.
Also, the whole deal about Michael's life force going into Jesus, and then going back into Michael, what big deal is that? It carries no personality traits. It is like running your PC off the wall socket, and then switching to an inverter in your car.
This doctrine is just plain goofy. It makes atheism look more sensible.