Experienced triathletes will likely be familiar with all of the training and racing information in the Diary. As for the logbook portion of the Diary, my only compliant is that it does not contain a section for weekly/year-to-date totals - which are very helpful in determining training progress as well as giving one a sense of satisfaction as to what has been accomplished during the course of a year.
Also- be prepared that well over 50% of the book is blank training diary pages. Although the book has good information it does not answer many of a first-timers questions that could be covered with more text and less blank pages.
Overall I would say the book is worth the money if you would like a training diary with a few pages of helpful hints on triathlons. It's a great way to log your workouts in an organized format that lets you see your progress over time.