@roz I don't remember exactly the cost when I was playing Clover but it was super low, somewhere between 1-3, I think.
However, there was a time when I was trying to bring someone in on a certain part of the metaplot, and that person started lecturing Clover on it and insisting that he had found an important artifact (looking at the object it was pretty clear it wasn't a staff made object, and we already knew where that artifact should be so he couldn't have gotten it) and no amount of IC or OOC saying "hey I really don't think that's what you think it is" would steer him from his belief-- unsurprising since he went on to get killed for his wildly off base theories and the way he treated other players.
During one of the conversations after I had decided not to just info dump and instead try hard to steer him back onto the correct course, he started OOCly lecturing me to put certain clues I had shared with him onto the Faith of the Pantheon @org. And how it was so much more cost effective AP wise if I would just put my clues onto the orgs. Which was factually wrong because it cost me tiny amounts of AP (though I still had little because my AP would go into @investigates each week) to share vs somewhere between 12-15 to put it onto an org and then brief someone if they didn't have the AP to do the briefing themselves.
It might just be that I'm on my fifth character now, but I'm way less enamored with @clues than when I first started playing the game. I'm more interested in clues for things that my characters are actively interested in, or in doing @actions, than the clues themselves.
I think I'm expressing that wrong-- I still love the lore and how creative all the staff are and how they seem to just infinitely be able to pop out little vignettes of lore via the clues. But I'm less interested in trying to hoard the entirety of it, and instead rather focus on things that are plots my characters are actively pursuing.
@Sparks Gave me one of the most chilling clues in the game (imho) but it's only so chilling because of the context that comes with that clue. It's akin to real world when you find out why the story behind "Ring Around the Rosie".