If HTML is supposed to be about semantics of the page, the NOINDEX tag should have been a part of every HTML specification, at least since server-side scripting became popular.

There is a lot of repeated text on each page of many websites, that really isn't part of the content, such as: "write your comment here", "next page", "previous page", "username / password", "permalink", etc.

I wonder if your website contains a word "permalink" in each page and comment, and there is one page that is really about permalinks, whether Google can tell the difference.