Your dad's no fool. I had a friend who made a living in the 1950's doing just that. These days, backing the 2nd favourite "place only" in races of 8+ runners on the betting exchanges isn't a bad scheme (especially if you add in a filter relating the available "place money" to the available win return on the same horse and do it only when you're getting "good value"). Sometimes the favourites become so short-priced, especially when they're tipped by the tipping services and premium-lines, that the returns for backing the 2nd favourite to place are quite disproportionate.