This was the companion reference for a statistics course in my MBA program. While the professor tested exclusively on his lectures, the book provided a unique resource that could assist with general class comprehension and served as a bilingual (Math and English) translator that could provide a different perspective on concepts to assist with learning. The professor insisted the book was unimportant for the class, but I regularly went back to it to fully understand and restate my statistics confusions.
Also, it's pretty dense material. Without a basis for understanding advanced math, much of this textbook would seem like gibberish. It's when it's used as a targeted reference that this text excels.