But yardage books have personality, and every one is different. While they're all designed to fit in a back pocket, some open like novels, while others flip like a steno pad. Some have fancy covers with alluring photos and computer-enhanced 3-D depictions of each hole; others employ line drawings that are a short step up from finger paints.
Golf tips are like aspirin. One may do you good, but if you swallow the whole bottle you will be lucky to survive.