In SDC, we have several profiles that define different aspects of Questionnaire definition. I have a few examples (and will soon have more) that comply with more than one of these profiles. For example, I expect one to eventually comply with the rendering, behavior, population as well as extraction profile. Right now, I can't point to more than one of these, which is a problem.

I understand that making polymorphic elements is a problem. One possible solution would be to eliminate the boolean and to say that if you can't point to a specific profile with the exampleCanonical to instead point to the ImplementationGuide as a whole - indicating that it's an example instance for the IG but not a specific profile. Another possibility would be to have both an exampleBoolean and 0..* exampleCanonical with an invariant that exampleBoolean can't be false if exampleCanonical is present.