Final answer:
It is true that every member of a development team should become familiar with the application domain to ensure effective design and communication within the team, although the depth of required knowledge might vary by role.
Step-by-step explanation:
The statement, 'Every member of the development team must become fully familiar with the application domain' is generally considered True. In the context of software engineering and development, it's essential that developers have a strong understanding of the application domain they are working in. This includes the business logic, the user requirements, and the overall market where the application will be used. Such knowledge is crucial in order to design and implement a system that meets the users' needs effectively and can innovate within the domain.
However, the depth of knowledge required may vary depending on the role within the team. For instance, while all team members should have a basic understanding, some might need to specialize deeply in certain aspects. Nevertheless, a comprehensive knowledge of the domain enhances communication within the team, ensures a better design process, and ultimately leads to the creation of a more valuable product for end users.