FWIW jandrewrogers has a habit of making deep and well-informed posts that usually end by saying something like "this research area / idea was already conceived of by industry 10--20 years ago, but due to financial motives or secrecy we never published".

I hope jandrewrogers, who posts a ton on HN and makes what seem like high quality comments can start to provide some links / references to make them more useful.

No, this is the frustrating thing about it. I only know about it because I was there. The volume of research is simply too large for a single person to write up unless they have nothing better to do. Best I can do is remind people that it is possible because I observed other people doing it first-hand.

There was a period of time when a lot of very impressive computer science and algorithm R&D was being directly supported by the US intelligence community, and they actively sought out unorthodox researchers — it wasn’t just PhDs, there were high school dropouts making credible advances on hard problems. While often not classified per se, most of the results were never published at the wish of the customer.

Due to a change in government policy around a decade ago, this community no longer exists. Most of the people doing that research retired, changed fields, etc. While I could write up some of this research in detail, it would require extraordinary effort and I am over-employed as it is. Also, a lot of it isn’t my research so I feel a bit weird writing about it. I’ve tried to convince a couple of my friends who worked in those programs to publish but they are just done, retired from it.

There are analogues in database communities, where really neat algorithms are freely traded that aren’t published in a formal sense.