This might already be known, but in my latest playthrough, I found a bug (I think) in Chapter 4, after finding out the truth and telling Arthur about it. After waking up in his room, I saw this:
"Arthur attempts to offer a sympathetic smile - the sentiment is touching but the result is more of a pained grimace, suggestive of his own anguish/suggestive of him feeling just as horrible as you."
I'm guessing the 'suggestive of X' lines are supposed to be one or the other, not both.