UMLR — Please make it clear what is being modeled behind the scenes for figures

As an example, it is stated here that
"The values of the ownedAttributes of a Stereotype (or its generalizations) applied to a model element can be shown in one
of the following three ways:
1 As part of a comment symbol connected to the graphic node representing the model element."
Later it says "Within a comment symbol, or, if displayed before or above the model element’s name, the Property values from a specific Stereotype are optionally preceded with the name of the applied Stereotype within a pair of guillemets. This is useful if values of more than one applied stereotype should be shown.".
I have not found within this specification in either the semantics or notation sections an explanation for what Comment symbols are representing with regards to this. Since there is the InstanceSpecification construct I do not believe this is expected to be manually typed.
I can understand one scenario where I create an InstanceSpecification to represent an instance of a Stereotype and I could have a Comment symbol represent only that. That could be extended to say that a Comment symbol should present information from more than one stereotype instance.Alternatively it could be meant that you define an InstanceSpecification and InstanceValues referenced by slots could reference the stereotype instances and that these should be decomposed as stated. However, 9.8.4 said, for an InstanceValue, that only the name of the referenced InstanceSpecification should be shown.
The specification must make it clear what should be modeled for a given figure, each time you present something that has not already been described, to avoid tool vendors coming to conclusions which could be different from those intended.