Johnjohn, I wish Father Steve would look in here; I can't help but think he might have some "inside information", so to speak! I did not read the book--not my thing at all. I looked up some summarizations of it: it seems to be primarily about how a pope (Pope?) gets chosen. So I offer the theory that it might be based on the expression about how hard it will be to fill someone's shoes, once the person has gone.