Ask HN: Questions on the HN Spam filter

A while back I put up an Ask HN, which did not get any replies. The post slipped off the "new" page in a matter of minutes. I figured it was probably a bad time to ask, so I posted it a second time (because I've seen others do it). Exactly the same thing happened. I'm not sure why I posted it a third time. Maybe just morbid curiosity. Same thing.

I forgot about it till I saw a comment today from samwillis telling me that my submissions were dead. My comments seem to be alive, so it appears that I am not banned. However, the three posts seem to have been either flagged manually or were caught in the HN Spam filter. I've seen the words "shadow banned" and "hell banned", but not too sure what they mean and whether they apply to me.

Since the post was an Ask HN with no links to any external site, (not a show HN) I presume the text of the submission is what flagged it down. Could it be the words in the title? I had to use the short form of words (difference and between) because the title could not hold all the characters. Could that be the reason?

Any ideas?

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My Three submissions

https://news.ycombinator.com/item?id=6608288

https://news.ycombinator.com/item?id=6555632

https://news.ycombinator.com/item?id=6539637

Comment reply from samwillis - https://news.ycombinator.com/item?id=6608446