Jost Nickel is a master of dynamics. The PDF contains dense systems of ghost notes between the primary backbeats. These exercises build the "Bonham" power while retaining the "Purdie" subtlety.
This is why the book is famous. You take the snare backbeat and move it one 16th note to the right. Jost Nickel Groovebook.pdf
Reading the PDF is not enough. You must follow Jost Nickel's specific practice rules: Jost Nickel is a master of dynamics
Drummers search for the PDF version for three specific reasons: Jost Nickel Groovebook.pdf
Within a PDF, you can search for specific page numbers or exercise types (e.g., "Half-time shuffle" or "16th note displacement"). This is impossible with a physical book.