My players are pretty strict with meta information.
I had three parties step into the same trap and die and I was like “guys, what’s going on!” and they were like “our new chars don’t know what our old chars knew!”
I was satisfied with that. In the end made PCs quick-witted enough to deal with the situation without meta knowledge.
I’ve said they are free to meta as much and as little as they want, it’s a lever they’re completely on their own for, I don’t mind it at all but to the extent that it takes away from their experience, they don’t do it. I have two exceptions to this:
Don’t do it in PVP situations. That’s the one time you really must stick to your character only knowing what your character knows. I’ve put the kibosh down when they’ve been like “but I do suspect they’re sneaking up on me”, I’ve been like “dude—you flubbed your check! You don’t know!”—I’d never do that for a monster but I did and would for PVP.
Don’t read the module. Obviously. That’d be a group-firing offense. After we’re done I’d be happy for you to check the module, but right now the only reason we even have me be the DM is so there can be unknown info to discover. Otherwise we could just whip out Mythic or Starforged.
