Awesome idea! I'll experiment with it in my projects. Doxygen is horrible, and looking at your example I can see it's far superior than Doxygen.
http://bloomberg.github.com/bsl/group__bslstl__vector.html
I'm no fan of Doxygen output, but it is used because it has proven to be the most robust for documenting complicated code.
edit: links
Also, whether the tool uses clang or a custom parser doesn't affect the HTML output in any way. I agree that using clang is interesting, but you seem to be depreciating Doxygen for all the wrong reasons.