Is the sunk cost fallacy always a fallacy?

[Edric O]

The sunk cost fallacy is always a fallacy simply because of its definition, but a given person taking into account their sunk costs in a given situation isn't necessarily always engaged in the sunk cost fallacy. "Sunk cost fallacy" doesn't mean "taking into account your sunk costs is always wrong". It means "taking into account your sunk costs is sometimes wrong". OOTS is trying to showcase one of those times with Redcloak.

In order for the fallacy to happen, there must be a better option that you are refusing to consider because of your sunk costs. When no better option actually exists, there is no fallacy.

For example, consider a gambler who absolutely needs to win big today or else something terrible will happen, and he has already invested a lot of money in a game which he has a low chance of winning. It was a mistake to invest so much money in that game, but now that he has - now that he's got that sunk cost - the best option is to continue playing, because he doesn't have enough money left to be able to afford to quit this game and start over with another game. His chances of winning may be low, but if he's in a situation where "you win or you die", it is rational to keep playing.

That's an example of taking into account your sunk cost in a way that isn't fallacious. When you've already invested all available resources into one thing and aren't able to start over with something else, it is rational to stick to your original plan no matter how bad it was. Because you don't have another option.

The argument is that Redcloak does have another option(s), and that's why his behaviour is based on a fallacy.

I'm not actually sure if that's true. Obviously The Giant intends it to be true, but it's not clear that Redcloak is legitimately aware of the existence of alternatives to The Plan that are clearly better. All the alternatives he has been presented with so far require him to essentially trust that the Humans/Elves/Dwarves won't just stomp the goblins into the ground as soon as they are able to. Would it really be more rational for him to trust his enemies than to continue with a Plan that his god assures him will work? Has Redcloak really been presented with convincing evidence that The Plan is an inferior option to some other alternative?