Thanks for the replies. Yes, I agree with Cyneheard as well and I'm not suggesting anything so extreme.
Fundamentally I think there should be a balance here between making spoiler threads easily accessible to lurkers, but not making them so open that players feel inhibited about posting privileged information in there that lurkers would find interesting.
Yes, at some level you have to trust other players not to cheat, and that level is certainly above the point where I'm worried someone is going to go off and create a fake account just to come and browse my spoiler thread.
However, if it's just a question of 'accidentally' clicking on someone's spoiler thread and having a quick read before backing out... that's a lot easier to imagine. Even if it's not actually that likely just the worry about how easy it is affects at some non-trivial level how comfortable I feel divulging sensitive info in my spoiler thread, especially if things start to get interesting (and as the amount of time I have invested in the game also accumulates).
There only seem to be a couple of people actively updating their spoiler threads and while obviously I can't speak for anyone else, I wonder if players might share their thoughts a bit more freely if they felt the forum was a bit more private. I have certainly received diplo messages in this game where players have explicitly requested that we not discuss details in spoiler threads precisely because it was sensitive, so I know I'm not entirely the only player who might have some explicit or implicit reservations.
Perhaps a good balance - if it's possible from a forum admin perspective - is simply to restrict
anonymous browsing. I.e. you must have an account and be logged in in order to view the spoiler threads (including the airstrip thread I guess).
That protects against most of the casual exploits I think, without really imposing any meaningful barrier to lurking. As a bonus side effect it might even increase lurker participation since if there are actually any anonymous regulars who haven't got around to registering yet, it might prompt them to do so and perhaps make it more likely that they'll start posting as a result. You never know.
Anyway, this is just my perspective and I'm not necessarily making any promises that I will write a whole bunch more if we actually do this...
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But it would certainly make it more likely without perhaps really costing us very much...
What do people think? And to the admins: is this type of restriction possible? (Must be logged in to read certain threads or subforum)?