Freeciv

The helptext for DEST_UNLIMITED is written so poorly that it has actually created public confusion and controversies.

While it's technically accurate in how it references the server code and its vars, there is no way a player can be expected to know how those vars are coded and what logic they are subjected to, without being a developer who investigates the code. But even in that case, it was coded in such a way that developers who looked at it were misled to believe an airport was required. The human language ambiguously leaves about 9 out of 10 people to also believe that.

I'm aware that some hypothetical ruleset that was never made yet, might create changes to the airlifting counter without even implementing an Airport, but A) no such rules exist that I know of and B) the great majority of all users see ubiquitous documentation everywhere else that airport in dest city is required, and then they read helptext that does not contradict this. Indeed, by not contradicting this, and only mentioning a counter, it makes them assume the default requirement of needing an airport remains in place.

Consider how SOURCE_UNLIMITED helptext, which mirrors the same language as DEST_UNLIMITED helptext, does not mention an airport is required but just assumes the user should know this by default, and then right after that, DEST_UNLIMITED helptext assumes the user will make no such assumption at all.

Most average users and many sophisticated users have been misled by the text. It should be very clear to a noob that DEST_UNLIMITED requires no airport.

I have seen proposals to change the text that did nothing to fix the above, and still assumed that users knew how the server code uses the airlift counter as a shortcut to check the requirement of an airport, making them work backwards through complex transitive logic to figure out an airport is not required.

The text should be very clear to a noob that an airport is not required in destination city. I'm happy to volunteer to find language that makes this clear while still being accurate to theoretical cases where rulesets augment the airlift counter without implementing an airport. Or just happy if someone else does it.