James-
My suggested solution: A special page perhaps listed on the Recent Changes pages at the top, to which people when they find grammatically and linguistically challenged articles can add them.
Why not just add the page(s) to [[Wikipedia:Pages needing attention]]?
I do agree that we have some users on en: whose every edit should be proofread by someone else. To effectively do so, you can simply use the contributions list for that user. To avoid duplicate work, you could say something like
"I copyedit [[User:Engrish]]'s changes"
to your user page and possibly other relevant pages.
Regards,
Erik