Hazarding a guess... redundancy and adaptability? Watson's not going to suffer damage to his neurons and still function, nor lose a swath of them permanently,

Hazarding a guess... redundancy and adaptability? Watson's not going to suffer damage to his neurons and still function, nor lose a swath of them permanently, but eventually relearn how to talk. Nor is it going to be able to ever independently 'learn' a new skill in general.