I know that Wiki is a work in progress, but think that a page in Wiki itself where we could note things that need further explanation or are missing from it could be helpful for the writers. I've just noticed that city status is not listed there as being a prerequisite for a great barracks and great stable, yet it's written twice that these can't be built in your capital.
Both of those are pretty recent changes, so I can see how the Wiki has so far overlooked them.
And while it might be nice to have a page on the wiki to note changes needed, you can also list them here on the forums.
I'll forward this to the responsible people and it'll be corrected asap. Thank you for reporting!