Transplantin a twins brain would still render the person a complete legume, not even the cranial nerve connections would be the same(sight, smell, hearing, touch of the face), let alone the spine nerves.
All the nerve wiring would be wrong.
DNA does not contain all the intricate nerve connections, just a meta-summary on how to build them.
I was talking about the cloning philosophical question (e.g. being copied by a Star Trek transporter), not the surgery which I agree sounds very risky.
