Having looked at the links (which I assume have been "fixed" and don't serve as examples any more,) I have no idea what this thread is about, specifically. Are people writing the same thing twice on the same Wiki entry, or similiar things on two different entries?
If it's the latter, then I have to admit to being guilty as well, to an extent. There's a lot of information up on WoW that you can find on two or more pages simply because it was pertinent enough to both to not (IMHO) justify linking to an entirely new page. For example, although I have a complete weapon proficiency table on the
weapons article, I will include class proficiencies on their respective class pages. My general rule of thumb is that anything that would take less than a full paragraph is worth explaining there rather than linking. (Putting a link within that text if there's more to be said is good, though.)
I may go a bit far, though, considering many times when a link to a sub-section of an existing article would do, I create a short blurb article to indicate specific terms.
Talent Points is a potentially superfluous article because there is already a short header for it in the
Talents article. I think part of this stems from an insecurity in using # tags, and part from a desire to be complete and have someone find information on exactly what they want without jumping through any hoops.