Your original issue with the article was that once you've "settled" an issue, there is no reason to argue about it. I pointed out that a number of people do not "settle" issues in the way that you describe, and that argument serves to update their information and beliefs constantly.

You stated that a mind "cannot be changed if it was never made." I disagree; one does not need to have an absolute belief in something to "change their mind." By definition, any update of beliefs is changing one's mind. My mind changes often, but usually by small increments. A key part of that is argumentation; I constantly seek out counterarguments to my own beliefs to see if new data or points of view will sway me. In the absence of that, I argue against myself, to see if I can find flaws in my logic and update accordingly.

By that logic argument, as described by the original article, is extremely useful for ensuring that one's beliefs accurately reflect reality.

To me, your position that an issue must be "settled" in one's mind (whatever that means, because I don't think you're perfectly clear on that) before you can be said to "change your mind" doesn't make sense.