This is a great question to consider! I think, however, we can only see the knight's response to his wife at the end of the tale as demonstrating his heartfelt change and transformation. Let us note the way that he initially responds to the old woman when she insists that he marry her:
"My love?" cried he. "You mean my damnation!
Alas! that ever any of my family
Should undergo such foul degradation!"
What is fascinating about this story is the way that the knight intellectually is able to give the queen the correct answer to her question of what it is that women desire most, and then has to realise the truth of this answer for himself in his own life, not just intellectually, but emotionally and with his heart as well. The knight's response to his wife shows his starting point, and, during the course of his conversation with his wife on their wedding night in their bed, we gradually see him change up until the point when he chooses to give dominion to his own wife and receives what he wants as a result. The force of the narrative would be much diminished if the knight was deliberately playing a game with his wife to give her the right answer. The Wife of Bath's message is cemented by his change of heart and his free relinquishment of mastery in his marriage.