
If they learn IC, and they tell others IC, that's fine. Sometimes it can derail plots, but it happens and sometimes it ends up being more fun going with the flow of things. But I don't like when people metagame their characters finding out my character's secrets, and I don't like when people spread my character's secrets OOC, because I generally like to keep a lot of my character's IC secrets as private knowledge OOC as well, because it helps avoid metagaming and also because it's fun to have unexpected twists and turns in the plotline to throw a curveball at whoever I'm RPing with.