UseCases are FunctionalSpecifications? in disguise. UserStories are the same thing. No, <<using>>, <<including>> and <<extending>> UseCases doesn't cut it.
ClassDiagrams relate classes because they are included inside another, they know each other or they extend another. Those relationships are not very well represented by cardinality, because it is not the same having a dictionary, a set or a list of objects, but all of them are represented using the same cardinality. ClassHierarchies? are not well represented in a diagram in which cardinalities are also represented.
UML is the antithesis of ObjectOrientation. On the other hand, CrcCards are a useful abstraction for modeling ObjectOriented software.
"UMLís segregation of the system model into multiple views is a major source of difficulty in capturing the system as a whole, understanding its parts, and being able to coherently follow the functionality it performs."