In recent years, command/shortcut keys have proliferated exponentially in WIMP menus. However, it remains unclear whether the substantial resources spent on programming the functions of such keys, have resulted in real and/or significant benefits for user interaction. This paper reports a study to determine user interaction patterns for WIMP user interfaces and users' performance in exploiting command/shortcut keys. Subjects were served a questionnaire, a paper-based test and an on-line task to assess their preference for a particular style of interaction and their performance in respect of command/shortcut keys. The results of the study provide a new perspective for software development managers who are confronted with limited human/project resources. The work will support better decisions and resource planning in connection with value engineering, and with the effectiveness and productivity of user interface programmers.