Summary
In all the detail which follows, it should be kept in mind that if Dr Wright really was Satoshi, a reliable private signing could have been performed very easily and simply. He could have signed a message on his computer, using the private key associated with the public key for block 9. That signed message could have been passed via a clean USB stick to, for example, Mr Andresen, who could then have run the Verify algorithm on his own laptop to determine if it was genuine. Nothing more complicated was required.
Against that simple point (on which the experts were agreed) there is a marked contrast with the complicated and elaborate procedures which seem to have been adopted by Dr Wright.