I wonder if successful con artists (or novel writers) have such a vivid imagination that they would be able to pass this kind of test. If you have such a good imagination that you can convince yourself you actually are in a make-believe world, does the lie become just as convincing as the truth?
Put another way, if a novel is so richly detailed that I feel as though I'm actually in the story, would describing my experience of that novel be interpreted by this system as truth or a lie?
I'd think it depends on the amount of time you've spent imagining this experience in the novel. If you have had enough time to vividly imagine the entire experience, none of the questions should catch you by surprise and you could answer almost as if you were actually there.
Regarding con-artists, yes I suppose it comes down to whether they can be as quickly imaginative on the spot as most people who are truthfully recalling an experience. That's probably where the inaccurate 15% of results come in.
Put another way, if a novel is so richly detailed that I feel as though I'm actually in the story, would describing my experience of that novel be interpreted by this system as truth or a lie?