When writers of fiction stray from their story, or seem to stray from their story, it can be annoying for readers, who usually just want to find out what happens next. Instead authors stick in a flashback or a long descriptive passage. Or they feed us more technical or historical detail than we really want to know. Or they simply change the focus from one character to another just as things are getting interesting. Even if the interruption makes the story better in the end, as it usually does, we readers can get impatient.
On page 94 of this novel, for example, Stuart is talking with Bertie, his six-year-old son, about girls, whom Bertie is convinced just want to push boys around. Stuart says, "You must remember that there are some very nice girls ... out there." At that point Stuart begins thinking about that phrase "out there." What does it mean? Where is "out there" anyway? Are the girls "out there" really any different than the girls Bertie goes to school with? This meditation goes on for a page, and while we would like to get back to Bertie, everybody's favorite character in the 44 Scotland Street novels, we don't really mind the interruption. At least I didn't.
On page 102 we are treated to a discussion of the movie Casablance between Pat and her father, Dr. Macgregor. This may have nothing to do with the story we are reading, but if you have seen Casablanca (and who hasn't?) you won't mind. And then they go from talking about the movie to talking about why people no longer talk to each other like they do in that movie, using complete sentences. (Even though that is exactly what Pat and her father are doing.) By page 104 the conversation, very much like a real conversation, has shifted again, this time to the topic of rudeness on the web and in traffic. All this has nothing to do with McCall Smith's story, except that this is always how he tells his stories. It may not be the most direct way to get from the beginning of a story to the end, but it certainly is the scenic route.