I think you're completely missing the point I was making. My point is that there is no such thing as under/over-reading a text when it comes to appreciating thematic harmony. What is important is first understanding what the intent of the text is. There has to be direct evidence of that. But once the intent is understood, making connections that support that intent further do not require intent, it only requires relevance. Which means if it works, it works. Is it intended? Who cares? By acknowledging that it works, and appreciating that, we build the vocabulary of our literary senses. This makes us more aware of what sort of thematic expressions work and how elements can harmonize each other. Did the person putting that together intend all that? Maybe, maybe not, but that's not important.
This is about how we can reconcile the approach of death of the author with the approach of needing to know authorial intent. It's easy, we just need to understand where the importance of authorial intent ends. It ends once the base intent is clear. If the intent is not clear, then anything drawn from it is completely subjective with no proven basis. It doesn't mean the reading is invalid, just weak. On the other hand if the intent is clear, then there isn't really such a thing as "over reading" it when we look for how things work together to enhance that intent. It becomes recognition and appreciation of how it all fits together, regardless of authorial intent.
There's a conflict between New Critics and New Historicists in terms of how to read a text (which in part is why we had Post-Modernism and Post-Post-Modernism, because the uncertainty of certainty because the lens to view things through for a while), so it's something that isn't readily reconciled when people have been working on this for the last 100 years.
Here's where I stand though, for what it's worth. Authors are "Gods" in the literal sense, inasmuch as they have absolute power over everything in the world that they create. Assuming the author isn't a total hack, most decisions will be calculated - who is the main character? Where is the story set? Does the character go through a dramatic arc? Then there will be the authors who care very much about the words that they choose (or the medium-relevant equivalent of "words") in order to provide details that both convey mise en scene but also thematic, metaphorical, or allegorical meaning. If author says that a character has a unkempt beard, the fact that the beard is unkempt could be a physical manifestation of the character's psychological or internal state. Maybe he's too tired or distracted to be bothered to shave or trim his beard. Maybe he's a slacker who is fine with not looking perfect. Maybe he's purposefully anti-establishment in not trying to conform to grooming standards. It matters in as much as you, as a reader, have to think why the author would use that adjective in the first place. Because the author could have used any other adjective, or none at all.
Of course this assumes that you as a reader trust that the author has carefully considered the words that they have written onto the page - not in the narrative sense, but in the idea that the author has crafted the story to convey a certain meaning.
In a way, prose writers have the most power of all creators because they can tell you exactly what they want to tell you and have exacting control over every single element of a story.
(I'd probably suggest that musicians are a close second).
I think where people get hung up is with film or other visual media, particularly those that are collaborative, because first there's the obvious question of what an author means when you have a production that is led by a single person but in which dozens if not hundreds of people are responsible for the end product. And then there are production realities that conflict with the actual story, but we have to basically just ignore them because it's clear that the story asks us to see the world as presented on screen as a metaphor and not to be taken literally.
The most obvious example would be that The Lord of the Rings is not set in New Zealand, despite the fact that it was filmed there and that someone who is native to New Zealand probably recognizes all of the locations that they used in the film. Most recently, Boston was used as a stand-in for NYC in the new Ghostbusters, but just because you might recognize Boston in the text doesn't mean that the film has suddenly transported the characters to an entirely different city.
(Vancouver, meanwhile, is a shitty hellscape that everyone wants to escape from, so Star Trek Beyond is set in the real world in that regard
)
I can understand the allure of suggesting that a text can be over-read, because human nature is to look for the "Occam's razor" solution to every problem and sometimes a blue curtain is a blue curtain (say, the movie producers found a house to shoot their film in but the home owners demanded that nothing be changed, at which point the set designer/director might compromise and keep the blue curtains due to a production reality rather than any real desire to have blue curtains in a scene). But the issue is that if we can agree that there is a way to "misread" a text, that means that a text CAN be read in the first place.
Or, I guess the tl;dr would be that a skilled author carefully chooses their words/images/sounds to convey a particular meaning that can be interpreted through a multitude of critical lenses. Particularly in the 21st century, when you can't ignore the fact that these lenses exist and where something as simple as the gender of your main character is going to be a point for critical readings of your text (again, the new Ghostbusters).
