Indeed, History is required reading for graduate courses in Rhetoric and Composition--not because it is the first attempt at a complete history, but because it has completed its history so well. While not comprehensive, as the writers note that now history can be, it presents a thorough account of the key events, publications, and professionals who are responsible for making the field what it is today. The "papertext," then falls into the tradition of an edited collection of histories--much like James J. Murphy's A Short History of Writing Instructin: From Ancient Greece to Twentieth-Century America--rather than David Russell's, Karen Burke Lefever's, or James Berline's single-authored historical efforts.
I'm ready for the 1995-1998 installment; might I sugges that it be published in Computers and Writing next year?
Regardless, any course introducing computers and writing pedagogy, introductory graduate course, or topics in writing curriculum should make room for this text.