In this case, they did communicate it, and the aforegiven Vogon reference is a mischaracterization. The naming convention is in the current IANA doco and Eggert copy.
Paul Eggert explained the continent/ocean plus largest city naming convention on a WWW page almost a quarter of a century ago. The WWW page was so well publicized that you can find its URL baked into at least four of the O'Reilly animal-cover books from the early 2000s.
* https://data.iana.org/time-zones/tz-link.html#tzdb
* https://web.cs.ucla.edu/~eggert/tz/tz-link.htm#tzdb
Paul Eggert explained the continent/ocean plus largest city naming convention on a WWW page almost a quarter of a century ago. The WWW page was so well publicized that you can find its URL baked into at least four of the O'Reilly animal-cover books from the early 2000s.
* https://web.archive.org/web/20011023074744/http://www.twinsu...
It was explained on Usenet and on mailing lists prior to that.