It is interesting what you have to say about the browser validating the
HTML documents it displays.
I agree (obviously) that documents should be validated. However, you
are suggesting that this should be done via the browser. This seems to
be more related to the authoring task. A browser user can do nothing
about a non-conforming document unless they are also the owner.
Additionally, it would be a waste of effort for an HTML "lint" to be
developed. There are a several public domain SGML parsers available and
these should be used to perform document validation.
Regards,
Steve.