Taken to its logical conclusion, and as there's no mention as to how this player knowledge is acquired, this would suggest you're fine with players reading the adventure before or as they play through it, or reading up on monsters at the table.So, on the list of house rules many players hate is my metagame rules. so, I'm tossing it out there.
The basic rule is: Whatever you the player knows the character knows. With the only real exception game mechanical rules. It's simple. But a lot of players dislike it.
I'll go out on a limb and guess that's not the case...which forces the question: where does the boundary lie?
Also, how do you reconcile this rule with in-game situations where the party is split up; in character neither group could possibly know what the others are doing yet at the table the players know this because you've played each group through? Do characters in group A suddenly realize the two in group B have fallen down a pit in the castle basement and can't get out, even though group A is hiding in the woods outside and isn't expecting group B back for hours?