Genetic evolution acts on a times scale much larger than cultural evolution. Talking about reproductive fitness gets a little complicated in a cultural setting. Memetics is an interesting idea becuase it changes our conception of what it is that makes each of us unique. In the past it was held that immortality, after a fashion, was obtainable through children. Memetics argues for a different emphasis.
Immortality is to be obtained in the procreation of ones ideas.
Having children is an inefficient way of reproducing ones own image, though many people find it rewarding for other reasons. Actually, the situation you described was detrimental to the Popes. In addition, this hypocrisy undermined future Popes ability to disseminate any memes whatsover, since they had the reputation of being disreputable sources. All in all, I'd say they screwed up, from a memetic point of view. But that's probably because they weren't thinking in those terms at the time, anyway.