Your definition of casual user is probably different from mine.
That being said, I think in most cases that if someone spots an error, they're going to click on the nearest, most convenient "Edit" link. And most of the time, that's not going to be the one at the top of the page. If they click the "Edit" link at the top of a mission, they'll be taken to the Mission's page to edit, which is where they want to be. They'll only end up looking at a transclusion reference if they click the "Edit" tab at the top of an article.
You're probably right about our definitions. At any rate, in my personal experience, when I started editing the wiki, I used the top page edit button. I still tend to use it most often, rather than section edit buttons. I don't know why that's the case, but it is what it is... and I operate under the assumption that if I do something, at least a few other people will as well. Which is why this change needs to be publicized.
Now, getting to definitions... I would say I categorize people into readers, casual editors, and editors (more of continuum than three distinct groups, but this'll work for now). A casual editor is someone who, seeing a typo, or something missing, or whatever, says "I can fix that!" and proceeds to do so. They generally don't create articles, they don't frequent the forums, they just fix minor things.
Now, when someone starts moving up to full on editor, they start creating pages, making larger edits, contributing more. However, they haven't seen the forums. So, in the case of Lt. Harris, for example, the user creating that page may not* have seen the forums. They saw an article that they could contribute, and decided to add it. They've only seen the majority of contacts, still in the old format, and thought "Hey, if I just copy this, and put in the correct info, I'll be done!"
So that's why this change needs to be publicized. How? I don't know, but it ought to be done, to prevent more articles being created improperly.
*I don't know if this is actually the case with the two people who worked on that article.