I haven’t taught a technical writing course in a while… I was thinking of offering it again sometime soon, so I was happy to see the recommendations on the rhet-comp making list,

Rhonda McCafferty:

There are also good excerpts in David R. Russell’s *Writing in the Academic Disciplines: A Curricular History*. The second edition was published in 2002, but if it’s history of the discipline you’re looking for, I’ve found that this has a good section on it.

Ann Brady:

Merrill Whitburn’s *Rhetorical Scope and Performance: The Example of Technical Communication *(paperback) and Kynell’s and Moran’s *Three Keys to the Past: The History of Technical Communication *(also available in paperback).

Michael Salvo:

Connors, Robert J. “The Rise of Technical Writing Instruction in America.” Central works in technical communication. Ed. Johndan Johnson-Eilola & Stuart A. Selber. New York: Oxford University Press, 2004. 3-19. Print.
Originally published in JTWC 12.4 (1982): 329-52.

Miller, Carolyn R. “A Humanistic Rationale for Technical Writing.” Central works in technical communication. Ed. Johndan Johnson-Eilola & Stuart A. Selber. New York: Oxford University Press, 2004. 47-54. Print.
Original Citation: A Humanistic Rationale for Technical Writing | Carolyn R. Miller |College English | Vol. 40, No. 6 (Feb., 1979), pp. 610-617 | Published by: National Council of Teachers of English | Stable URL:http://www.jstor.org/stable/375964

Andrea Beaudin keeps a nice annotated bibliography: http://bit.ly/R5KWcU