We see Madara in 606 disconnect from GM life support and at that time should have died with a Sharingan. Depending on your belief of how ET works shouldn't Madara have been revived in the state he was in at death (ex:Nagato, Chiyo, Hanzou) but wait he has the Rinnegan and is also young. Now, many folks believe Kabuto restored his youth. Fine, what about the Rinnegan? That's just how ET works. Fine, what about Nagato's depleted form. Why would Kishimoto make it this complex. Until the war only Orochimaru had used ET there is no reason why Kishimoto would need to do it this way. He could have easily made Edo Tensei restore the individual to prime abilities, period. There must be another reason for this. Any theories?