Predicting how a collection of baseball players will fare in advance is something that Shandler understands. If you buy the book with the expectation that Player X will get N home runs and M RBI and P stolen bases, etc., that's the wrong idea. If you buy the book with an understanding that there are indicators that correlate well with performance, then you can put together a strong fantasy baseball team with this book in most years. (You could choose too many players out of the wrong 20% of the population.)
I have used Ron Shandler's book for years, and it has always been excellent. Even in a down year for me, the book has been on the mark, in general. One of the nice things is that Shandler is up front with his explanation of the statistics he uses and how he uses them.
There are lots of preseason fantasy baseball publications. Better to get one excellent book than a bunch of crappy ones.