Upload & Sell: Off
There are a few considerations, but before touching on them, if you like the photo vaflower, why not see if you can obtain a print, either from the publisher or Steve?
Now, one thing is design - a DPS can break up a section in an arresting fashion, as it can be unexpected. Personally speaking this is a poor image to see so large, not enough detail that needs expression.
Second, this is portrait mode, most photo books work best in mild landscape mode, like 11x13. If it is all people maybe an exception can be made.
Third, what can work very well is 1.25 to 1.5 page images, especially if the subject matter gives an harmonious look to this layout. If the book contains text (and it should IMO), a column of text can augment this look. Not 'show don't tell' but show and tell'. This idea would work well for this image, and I don't like the white space layout as it is - rather crude. For something suitable no white space at all works better.
Maybe the explanation is simple - magazines love DPSs, and it morphed from there into this photo book design.