So basically what happens is:
Unit gains enraged
Unit gains ability to hide nationality
Unit is taken over by AI
AI checks to see if hiding nationality is a "legal" move
- if so, AI hide's nationality and goes off to attack the neighbors
- if no, AI moves unit. During each move, the AI again checks to see if hiding nationality is a legal move again
Unit loses ability to hide nationality when the enraged promotion is removed
The question then becomes, will the AI utilize such a promotion to hide nationality?