User blog comment:Rupert Giles/Layout Changes: Breakpoints and Typography/@comment-13918697-20150527072158/@comment-452-20150527105800

Thanks Sir Goreth! "elements which are styled with a more specific selector than .WikiaArticle will not be affected by our changes."

This is the key phrase there, because:
 * ".WikiaArticle" is not a more specific selector than ".WikiaArticle"
 * ".WikiaPage .WikiaArticle" is a more specific selector than ".WikiaArticle"