When dealing with old requirements documentation from a legacy system that lacks current information, which technique should be used?

Using document analysis is an effective technique when dealing with old requirements documentation from a legacy system that lacks current information. This approach involves systematically examining existing documentation to extract relevant information, identify changes that may have occurred over time, and determine the current relevance of those requirements.

Through document analysis, you can uncover insights about the legacy system's functionality, constraints, and past decisions, which can then inform the development of new requirements or the necessary updates for current systems. This technique allows stakeholders to leverage valuable historical knowledge while also highlighting discrepancies or gaps that may need addressing due to changes in business needs or technological advancements. It provides a structured method to navigate outdated information, ensuring that any legacy insights are carefully considered before moving forward with future developments.

In contrast, other options such as not using the documentation altogether, simply surveying the available information without structure, or conducting interface analysis do not capitalize on the potential knowledge embedded in legacy documentation, which is still relevant when assessed properly.