A complete rework of a document.
Over time, wiki content becomes dated and confusing over time from multiple uncoordinated, inexpert and generally clumsy authors. See Cruft. The general editor climate of a wiki separates random editors from ownership of a page, especially with a wiki infested by assholes, so various edits are hesitant and disconnected from one another like they are gripped by a kind of chilling effect.
Eventually such pages will need to be completely reworked. This is something like the "1.0 to 2.0" software revision, where the hard lessons are learned in version 1.0 of a program and things are essentially rewritten from scratch to make version 2.0.
A particularly bold wiki gnome is the most likely person to see and tackle this problem.