The generic stuff: They are his answers after all - my approach would be not to mess with them until really necessary or at least until I would be confident that he would not disagree with the edited content. As he expressed that he does disagree, minor edits not contributing anything significant to the subject should not be made.
The specific stuff: If he feels the need for headings, he should be able to use them. We also should take into consideration that serverfault only has one type / one level of heading formatting here - it is not his fault that the template is ugly.
As a side note, I really feel that the readability of his posts in fact do benefit from the way he is using his headers. A thing perceived as "ugly" and "screaming" by some of us, might be quite fine with others.
The linkage stuff: he always names the article author along with his reference, so he obviously is not hiding anything - especially as his user name is constructed from his initials.
The personal appeal: Live and let live.
The edit: I really would have been surprised if nobody had discussed this kind of a problem here yet, but there even has been a blog post at SO on edit wars to make things clear. Of course, there are always two sides in such a controversy, but the participants should not forget that one of the two sides is them. Some excerpts with appeals which obviously badly need repetition:
As it says on the sidebar of every edit page, here’s what makes up good editing practice as we see it on Stack Overflow:
[...]
- Always respect the original author.
[...]
Editing is welcomed and encouraged. However, if the author of the post is resistant to your editing changes, even a perfectly legitimate edit based on the above rules, be the bigger man (or woman) and let them have it their way.
[...]
Remember, we’re all adults here .. in theory. Please try to resolve edit disputes through simple communication, hopefully the kind that doesn’t involve being rude to your fellow developers. It says “Be Nice” in the faq for a reason.