Davis Rogan, a favorite musician and songwriter, introduced me to this expression, generally translated as the wit of the staircase. These are the things we think to say too late. In this case, it's not a lost opportunity for wit, but a missed chance at candor that bothers me. I was asked Monday night if I chose to use a real-life inspiration for WTDK because I thought it would help me sell more books.

As a longtime reporter, I was always amused by people who believed that certain stories -- usually stories they disliked -- were printed because they helped to sell papers. You know what sells papers? The sports section, the comics, horoscopes, certain columnists. Newspapers across the country are putting less energy into investigative reporting, based on recent reports at Romenesko, and I doubt a single reader has phoned in to protest. But let a newspaper drop, say, Rex Morgan M.D., and see what happens.

This question left me especially nonplussed because part of my book talk on this tour concerns how difficult it is for most of us to have true empathy for the victims of crime. I often speak of the Missouri case, the dual kidnapping uncovered only a few months ago, and the hateful things that were said about the boy who had the misfortune to be held by his captor for several years. I talk about the human need to disengage from stories that are too close for comfort, the way we all read or listen to news accounts looking for the detail that allows us to believe that we are safe, that life isn’t as terrifyingly random as it is. ("I would never go to that neighborhood after dark." "I would never let me child ride his bike to school." That kind of thing.) I also stress the difference, in my mind, of being inspired by a real-life story and basing a novel on one.

Here's what I wish I had said: "If I were to choose a real-life story in order to spike sales, I think I would pick one in an area where I don't sell so well, not my home state of Maryland."

Ah well, it's good for me to be nonplussed these days. The cold roars on and, for two nights running, I've managed to croak my way through presentations only to have a spectacular blow-out as the hour draws to a close. Today will be especially challenging -- class at Goucher and a booksigning/talk at Politics & Prose. If my voice doesn't get better soon, I might start seeking audience volunteers to read passages from the book.