What is so amazing about Gruber's SAT Math Workbook?

<p>I’m looking through it and half of the book is just teaching elementary concepts, not even in an “SAT way”. The next half is just practice questions + explanations. Sure, every math book needs a toolbox section but it seems as though this is just a “Math Workbook” with SAT strategies and beginner’s stuff at the end :dahell:</p>