It's probably best to avoid Use Cases, (R)UP, and the associated process and document bloat, but a nice diagrams here and there can really simplify discussions.

It's probably best to avoid Use Cases, (R)UP, and the associated process and document bloat, but a nice diagrams here and there can really simplify discussions. Class diagrams are more or less useless, and it's mostly requested by non-professionals that can't read code. Use case diagram are more or less irrelevant too, with just an actor connected to one or two things. I think that it's mostly administrative (in house) systems that models reality and complex processes that benefits from a modest dose of UML diagrams, not typical applications.