I find the way the "belongsTo" relationships are drawn in the domain class dependencies diagram a bit confusing. While the groovy way of defining the relationship is kind of in line with the DB way (the child "owns" the relationship and points to the parent), the diagram draws the relationship with, what seems to be, a UML composition line.
The problem is that the diamond is on the other side of the relationship. In UML one has the filled diamond on the parent's part, while in the grails diagram it sits on the composed object's part. In the attached image, the user would have multiple NotificationRegistration entries, but the diagram (read in UML key) would hint the opposite.
I'd prefer to have the diagram more in line with the UML way of showing things. If not, maybe the relationships should be drawn with plain lines (and, eventually, some text decorations to indicate semantics), so not to be confused with the UML notation.
What do you think?