Okay, what is that, how to you get to it, and what interactions does it have? The problem with referencing the Ranger ability is that it doesn't establish any rules by itself -- you're just inferring a rule because that's how you see that working. To me, it's another place where there's a nearly redundant statement that exists to cover corner cases. Normally, an invisible creature is detected unless they're hiding, but some cases may exist where the GM may rule otherwise. Here, the Ranger ability works by saying that within 30', it doesn't matter what the situation is, the ranger detects the invisible creature unless, and only unless, it is successfully hiding. It doesn't, by itself, establish a game condition found no where else in the rules and where the rest of the rules would actively disrupt such a condition. Again, if this third state exists and is associated with invisibility -- why doesn't invisibility say anything about it?