I think this is just a semantic argument at this point, but to me what you mention isn't evidence of the annotations doing anything. They make it possible for t

I think this is just a semantic argument at this point, but to me what you mention isn't evidence of the annotations doing anything. They make it possible for things to be done, just as I said. The distinction I'm drawing is to statically-typed languages where simply adding annotations will actually change semantics of the program (e.g., by forcing a downcast or something). But you're absolutely right that annotations can be useful for many things!