Yes I am familiar, hence why I think you are wrong.
You seem to be familiar with the pop-culture version of "the scientific revolution", the problem is it's not actually what happened.
Ignoring the question of whether or not a "revolution" happened, rather than continuous and gradual evolution, if it did happen it was around the 17th C and happened within a field called "natural philosophy" and remained "natural philosophy" for 200 more years.
People didn't go "hey we've invented this new thing called science and are now scientists not philosophers", while some philosophers said "noooo, we hate rigour and refuse to join you". Science/scientist became the preferred terms in the 19th C, and even in the mid 19th C natural philosophy was used synonymously. Prior to this, science simply meant any disciplinary knowledge, not a specific kind of field based on experiment.
So unless you think the scientific revolution actually happened in the mid-19th C, what you are seeing is a rebranding of a field that had already changed.
There were certainly major changes in natural philosophy when people adopted experimental methods, but "science" was simply a language change that happened centuries later. It is an error to look at history teleologically based on what is now considered true and assume that science replaced natural philosophy in the 17th C.
If someone creates an artificial and unnecessary boundary as to where one can apply the standards and principles of scientific investigation, I can't help but try to understand why.
You could always interpret things in good faith rather than construction your own fictions based on prejudice. You could also just remember the half dozen times I've told you the same thing and you wouldn't have the need to. Alternatively, if you forget, instead of mind-reading you could just ask.
But, hopefully this shows you about how we interpret the world through narrative, and the stories we tell ourselves have a significant impact on the reality we experience. We can't help but give meaning to things and fill in the gaps, and we see often things as we want them to be not as they are.
Also, unless you think there are no limits as to where scientific methodologies can be applied though, the distinction is certainly not unnecessary.
All that is required is that the methodologies are appropriate to the subject or question at hand and that such methodologies make best efforts to mitigate the potential error of the investigator.
People generally don't view a book on art history as "science" no matter how methodologically thorough it is.
If everything can be "science" you are basically reverting to the traditional use of the term, not the post-19th C one on which your argument is dependent.
If anything that involves rational thought about reality is "science", then your argument is basically tautological. Philosophers are "bad" because they refuse to think rationally about reality!
I do not disagree that due to human nature we as individuals identify with those who share a particular value or choice and will naturally see opposing views as antagonistic. And this will always be true. But your stating the requirement for fictional narratives hasn't solved this issue. You mention the American right above, yet whatever concepts are involved to bind and define all Americans as American does not prevent division over other ideas and concepts. This in the eternal problem, accommodating, reconciling, and compromising over different subjective value preferences. Relying on or requiring myth does not solve the problem.
Nothing solves the problem as it is based on fundamental characteristics of our cognition and genetics.
How do you think replacing fictitious myths with 'not true' ideologies makes any progress in this regard?
Along with the Michael Oakeshott quote from before, the other quote that best explains humanism is from John Maynard Keynes:
"Bertie [Bertrand Russell] sustained simultaneously a pair of opinions ludicrously incompatible. He held that human affairs are carried on in a most irrational fashion, but that the remedy was quite simple and easy, since all we had to do was carry them on rationally."
As to convincing people to go against their perceived best interest for the common good would be to convince them that the common good better meets or protects their perceived interests. If enough are convinced then there is sufficient power to institutionalize those beliefs and enforce them.
Ideology is how you explain to yourself how the world works and the way it should be, and how you try to persuade others that you self-interested and subjective preferences are in fact altruistic and universal.
We persuade others best when we pretend that this is not the case, self-deception is hardwired into us for this reason.
My whole argument would be exactly this, to acknowledge from whence our ideologies and myths originate, why they originated, how they function in society, evaluate the merits of any values expressed and make determinations about those value choices solely on their affect upon society and make any necessary changes and adjustment. In other words, no ideology or myth should be preserved solely on the grounds of tradition or claims of inerrancy and immutability. We learn to recognize the merits of particular value choices on their own merits and affect upon society and justify the adoption of them on those terms.
From where do you think your ideology and worldview originate?
As for establishing 'merit', you can't step outside of your frames of reference. Many of your moral axioms are the direct or indirect product of myth (in the fictitious sense of the term). The merits of any system are judged by these moral axioms. Humans are value pluralist, which means a range of value systems can emerge from our genetic makeup and environment, but there is no objective way to say one is better than the other as all are equally 'natural'.
Your 'progress' is basically moving from "I believe in XYZ because it is god's will" to "I beleive in XYZ because my ancestors thought it was god's will and even though I don't believe in god any more, I quite like their value system so am just going to pretend I arrived at it myself and it is now rational".
Very few ideologies are unchanging and immutable anyway, even those that nominally claim to be unchanging and immutable.