The User Edit Method for Evaluating the Usability of Documentation
http://www.stcsig.org/usability/newsletter/0610-useredit.html

Wilson, Chauncey E.
Usability Interface
2006

Abstract:

A 'user edit' (also known as a 'usability edit') enables you to evaluate the usability of documentation (Schriver, 1991). Participants in a user edit study can either think aloud as they use the documentation to complete tasks or they can mark up the pages of the documentation to indicate where they had problems. The think-aloud protocols or marked-up pages are then reviewed for usability problems. The user edit report lists the problems and recommendations about how to improve the usability of the documentation.