in reply to XML-style readmore not being parsed

On a semi-related note, speaking of well-formed SGML, is there a good reason why the <readmore> tag appears in the HTML that's sent to the browser? The browser can't do anything with it directly, it makes it even harder for the page to validate, and it prevents tools like HTML-Tidy from processing the source until the <readmore> is manually removed.

While I understand that there are good reasons to be able to figure out where and if a page contains a <readmore>, why couldn't it be transformed to <!-- readmore --> before the HTML is sent to the browser?

Then again, I'm sure there's probably a good reason and I just can't think of/find it.

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