Since we're Plato-izing. This construction is a question: "I'm Still Here" is begun as sung dialogue, i.e. a mimetic premise of self-expression, and then when Carlotta segues and begins to ruminate, it becomes diegetic? Narrative commentary, or a sustained annotation to what she says in the set-up and begins to sing? If I'm getting this backwards, help me out here. This is an informative way to look at text and performance.
(Sorry for my multiple misspelling of diegetic throughout the thread. My fingers don't like to type the word.)