I suspect (but am open to correction if wrong) that their concern is that the exact phrasing might force them into a position of either:
--- having to allow those features to work everywhere every time, or
--- having to disappoint one or more players who, having quite reasonably interpreted 'always works' as the intent of the phrasing, expect to be able to play it that way; and thus come across as the bad guy when I deny their argument.
Well, that's why I've been suggesting ignoring the exact phrasing.
Or using another, completely legitimate,
actually primary definition of the word "know" that doesn't
add the word "personally" to the sentence.
Or focusing on the feature's actual purpose (the contact instead of the messenger; getting ship's passage instead of calling in a favor) instead something written into the feature in what (to me) is
clearly an example, not an exhaustive list, or making up the meaning entirely.
I know that'd be my own concern, were I to have missed fixing that terrible wording before starting play.
Yeah, well, hindsight woulda shoulda coulda, etc. I'm sure that the '14 books would have quite a few changes if the players got a hold of it before publication. It would have an actually useful index, for starters.
And were I a player, by the wording given I'd naturally expect the feature to be always-on no matter what because that's what it says and then probably get somewhat hacked off when the DM shut the feature down when the fiction disagreed with the rule. And that's not fair to the DM, who has unjustifiably been put on the spot by badly-written rules.
And this is one of the other things I've suggested doing--
ask the players. "OK, you're in a land you've never been to before. How do you expect to use <feature>?" Because often, the players have really interesting, useful, and sensible ideas. And often, they'll go "Oh, yeah, it wouldn't make sense for me to use it here." And if they
do have an idea that's really stupid or illogical or overdone[1], or is one you don't like or that violates your understanding of the RAW or RAI,
then you say "Not this time, and we can talk about it more after the session" or even just "No."
Sure, there are argumentative players out there who won't let it go--but in my experience, that's usually because they have DMs who strip all their power and input away to the point they
only have RAW to back them up. Either that, or they're just argumentative jerks, in which case they need to be talked to.
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[1] And can't be turned into a plot hook, of course. "Yes, it
is a bit strange that there's always a ship at every port that's willing to give you a ride. What did you say your passive Perception was again? Hmm." And then you start thinking about what sort of eldritch creatures are manning the boat and why, exactly, they're always there for the PC. As someone who primarily runs horror games, I would be
giddy if this happened in one of my games.