I know the basic philosophy of wiki is not to restrict, but be as open as possible. But still, that won't work always. In Wikipedia, even if there's error in some article, that won't affect anyone critically. But in a corporate wiki, the information may critical. E.g. our wiki deals with configuration information of our s/w for banking and telecom sector. if wrong information is there and if anyone uses that information to configure the s/w, that may lead to error or unwanted results.
I find it is usually OK to mark things like that as draft, and include a warning saying that the documentation may not be complete/accurate yet. The upcoming stable version stuff may work perfectly for that. Mark checked articles as complete, and have everything else considered draft (possibly with a warning).
V/r,
Ryan Lane