A good story has many levels of meaning. That is certainly true for me as the storyteller in this "fish" story. We were so caught up in the drama of bringing the fish in that only the wife realized that her husband was dying. Magicians use misdirection to entertain but, all too often, we miss the deeper meaning of an event or even a relationship because we focus on the superficial.
For me, as his son, a more compelling reason for telling the story is my Dad's spoken response and his unspoken vision of a good death for himself.