The install wiki is full of outdated information that causes people to install outdated and old methods of doing things. So I wouldn't advise people to use it, other than the fact there's no other option.
I find that hard to believe. I've always found the Arch Wiki to be excellent and very up to date. Do you have any examples of articles which document outdated ways to do things?
If you have found incorrect information, please edit the wiki to improve it.