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What if you resubmit a blog post that's picked up 150 more comments since it was last posted? How would HN tell the comments apart from the article text?
What if someone submits a blog post that heavily quotes another article that's been submitted, in the process of rebutting it, and ends up being a 80% match?
What if you include the full text of moby dick, in a display:none <div>? What if the page loads the text of the article with javascript? Would the HN submissionbot have to render CSS and javascript?
Most resubmissions are submitted by people other than their authors, who are typically not in a position to change any bytes of the content.
In the present case, speaking as the last person to submit this one (more than two years ago), I don't see that there's any harm in it at all. If this is still interesting two years since it was last discussed on HN -- which clearly it is -- then good for the submitter, who has provided the HN audience with something interesting to read.