Track information about persistent attributes overridden within a hierarchy. E.g.

@Entity
@Inheritance( ... )
class Root<T extends Root> {
    ...

    @ManyToOne
    public List<T> getTs() {...}
}

@Entity
class Sub extends Root<Sub> {
    @Override
    public List<Sub> getTs() {...}    
}

We could do useful things here like limit the joins needed in a SQL query for Sub to just the Sub table for references to Sub#ts