Also, they could just split the book in half at whatever is the most logical breaking point, and print two approximately 264 page volumes. It would probably make physically handling it easier too...
Edit: Just finished downloading and took a look at it. Splitting it into a "1975-2000" volume, and a "2000-2014" volume seems to make the most sense. That splits it almost exactly in half by page count, as well.
Two volumes are perfect, at that junction, between "classic" and "modern". I've also split the PDF into 2 smaller PDF files, to make it easier to load on low-end system.
Edit: Just finished downloading and took a look at it. Splitting it into a "1975-2000" volume, and a "2000-2014" volume seems to make the most sense. That splits it almost exactly in half by page count, as well.