We have presented our technique involving index cards and roleplay to help determine use cases. We were looking for ways to make use case development more active, accessible, and better guided. We based our technique on the established CRC card technique used for object-oriented design.
Our technique is lightweight and low in formality, but it is easily employed and in our experience has been very effective. We did get the benefits we set out to achieve: the technique gets people involved rapidly, and guides use case development in a sensible way. We also found the techniques were effective in exposing potential flaws and anomalies in use cases, and was especially helpful in determining the system boundary.
Other benefits related to our adoption of essential use cases. These use abstraction in their steps by emphasising user intention and system responsibility. We found these characteristics worked well with our use of index cards and roleplay, and made use case analysis both easier and more powerful. In particular, the identification of system responsibilities provides opportunities to better guide object-oriented design, and leads to better traceability between design and requirements.