IVE: Instance "instance of" misbehaves
there are instances that misbehave: the "instance of" attribute is greyed, and it is possible to add interfaces to the instance (while normally the tool prevents it)
That happens when reloading a model that constains the instances. when instances are created (from Shared Types) they are well protected (not possible to add interfaces) but if you save and reload, its then possible to add interfaces.