Earlier quoted context omitted.
this is exactly my point html is not precisely defined
I think you're missing the point that it is defined, the current html5 spec says that implies the existence of , implies the end of , body tags imply the end of and the start of etc. HTML5 is not XHTML. Title Heading expands to Title Heading
if `A Heading` is equivalent to `A Heading` then this means the language is not precisely defined