The problem I see with these rules is that you're only going to read new books. I use a heuristic that the best book about a given topic was most likely writte

The problem I see with these rules is that you're only going to read new books. I use a heuristic that the best book about a given topic was most likely written half as long ago as people have been thinking about that topic. People write more books now, but they get less interested in old topics as time goes by, and those effects tend to cancel out.