If something is nearly impossible to discern within the confines of the game, ...
But that is different for everybody. I had no problem figuring out some stuff others found too difficult and other way round.
Did you have play testers without any kind of walkthroughs?
I'm quite sure they had.
Actualy we didn't. It was part of the play test. During the first run, you need to get a fresh look on the game and see how people react while they play, then tweak the gameplay to make them feel the way the design was suppose to. If Alec or Derek would've provided us with walkthrough, we would not have been able to get that "virgin" feel.
Of course, after the first runs, we ended up using some walkthroughs and guides to test the funcitonalities and see if everything worked like planned. But, at first, we started with nothing, just to see how we felt.
The first time I played, I missed a lot of stuff. Afterwards, I saw pretty much everything. Some testers found everything possible the first time around tho (at least if I remember well

) . In the end it depends on the player. Some like to explore, others don't (or others aren't exploring thoroughly when doing so). I wish I could give you some personal example but the version I first played is too different so my examples would be irrelevant

And I liked the fact that you could go where you wanted to when you wanted to. I feel that it makes the world more believable. You know it's a stupid idea to wander off in a strange place filled with danger, without any source of light, but nobody is gonna stop you from doing it, like in "real life"

. Well, it's my opinion