I am reporting this text, quite recently published (April 2015).
the narrative adopts a writing style that is clear, simple, fast-paced, fluid, and free of specific terminology for industry professionals; all in all, the evolution of every single historical event and the transition to the next seem very clear in the writer's mind (who is a journalist, not a musician).
It describes, e.g., effectively the transformation of various ragtime styles, which from the classic (of Joplin) to the evolved (of Jelly Roll Morton) results in stride (of J. P. Johnson); etc.
ScalaQuaranta
P.S. I haven't finished reading it yet; I am just finishing the part dedicated to "ragtime."
Ciao