Think about it like this:
When I KC a Wharf, I get this effect:
-+6 Cards and +3 Buys this turn
-+6 Cards and +3 Buys next turn
NOT
-+2 Cards and +1 Buy this turn
-+2/+1 from the duration, and another +2/+1 from playing it again this turn
-+2/+1 from the duration, and another +2/+1 from playing it again this turn
-+2/+1 from the duration
That would just be silly.
So why would Outpost work that way?
KC-Outpost simply tells you three times to take a single extra 3-card turn. As a reminder, I guess.
I think that's false though, isn't it? When you play a procession/throne room/king's court, you're playing the card X times in order, meaning that you resolve the card fully before playing it the second/third time.
Sure for a wharf the total effect is +6 cards and +3 buys now and on your next turn, but how would you solve a pearl diver? If the card was simply multiplied by 3, you'd get +3 cards, +3 actions, then you'd look at the bottom of your deck three times, putting the card on top or not.
Pearl diver explicitly doesn't work like that though, it's:
- king's court a pearl diver
-- pearl diver gives +1 card, +1 action, now you look at the bottom of your deck and you're allowed to put it on top or back on the bottom
-- pearl diver gives +1 card, +1 action, now you look at the bottom of your deck and you're allowed to put it on top or back on the bottom
-- pearl diver gives +1 card, +1 action, now you look at the bottom of your deck and you're allowed to put it on top or back on the bottom
So when you play the king's court on a wharf, you are also explicitly playing the card three times and not merely multiplying effects:
- king's court on a wharf
-- +2 cards, +1 buy, set up later ability of: at start of next turn, +2 cards, +1 buy
-- +2 cards, +1 buy, set up later ability of: at start of next turn, +2 cards, +1 buy
-- +2 cards, +1 buy, set up later ability of: at start of next turn, +2 cards, +1 buy
Using a king's court, throne room, or procession on an outpost and having both cards stay in play is because it's setting up some effect multiple times. If it wasn't, then the KC/TR/Pro would be discarded during this turn's clean-up phase.
For example, consider a three card hand of Throne Room, Haven, Silver, and you have nothing in your deck or discard pile:
- play throne room, choosing haven
-- haven is played the first time, giving you +1 card (failing because nothing to draw from), +1 action, and you are forced to set the silver aside until next turn when it'll be put back into your hand
-- haven is played the second time, giving you +1 card (failing because nothing to draw from), +1 action, and you fail to set aside a card because you don't have any in hand
--- at this point, throne room is no longer attached to the haven because it isn't doubling its duration effect, so it will be discarded during this turn's clean-up phase (see throne rooming a tactician for reference)
--- haven has successfully set a card aside, so it will be left in play this turn, and discarded during next turn's clean-up phase
Thank you for the response though, and I do apologize if I've missed a crucial rule anywhere.