The XML/HTML task force concluded that there is a dichotomy between "HTML parser in tool chain" vs polyglot.  See: http://www.w3.org/TR/html-xml-tf-report/#uc01

However, I believe this is a false conflict since an "HTML parser in an XML toolchain" could be made to output polyglot markup. Thus there is not really a conflict here - one can have both!

By adding this fact to the polyglot spec, we also take issue with the belief that polyglot markup can change the face of the Web - from tag soup to well-formed. 

Also, since some are very eager to promote the HTML parser solution, why not promote it in polyglot markup as well?

Also, a related use case is that polyglot markup is easier to exchange between different authoring tools. E.g. between a HTML WYSYWYG editor and an XHTMNL WYSYWYG editor. 

So, at the end of (or after) the paragraph that currently begins "All web content need not be authored in polyglot markup", add a sentence such as this: 

"For authors that, in order to consume non-well-formed Web content, place an HTML parser in their XML toolchain or which use an XHTML editor that can import HTML, it may also be an option to have the HTML parser transform the the Web content to polyglot markup in order to combine the benefits of the HTML parser in XML tool chain solution with the benefits of Polyglot Markup."