They spent years teaching him how to be Picard, or hard wired him how to be Picard into his dna before they junked the idea... Did they say how old he was when they threw him in with the Remans and considering the forced maturation involved in cloning how mature, physically, emotional andintellectually that made him?
You know what happened?
Picard kept turning own promotions.
Replacing a Captain is bullshit.
Replacing an Admiral is endgame.
There was a flash back of Shinzon from when he seemed to be 12 or 13?