ok, even if we forget about realism (and even consistency) for a moment, the fact remains that the way retraining is implemented gives the player incredible opportunities for abuse, and a huge advantage against the AI simply because the AI doesn't "think". There are several ways to benefit from those opportunities (several were only pointed out by motorhead).
IMO, this is a _bad_ way of giving the human an advantage (not that he needed one), and is producing a significant imbalance in the game.