https://news.ycombinator.com/item?id=23852177 https://news.ycombinator.com/item?id=23852177 explains it, with a quote from the article. They weren't able to map

https://news.ycombinator.com/item?id=23852177 https://news.ycombinator.com/item?id=23852177 explains it, with a quote from the article. They weren't able to map the whole thing, because of repeating patterns. That's now starting to change.