> [1] I read years ago that border guards in some countries use a similar technique, because if someone is being deceptive, it's unlikely they can handle a random walk to an arbitrary depth of detail.

Such people are not necessarily deceptive; in my experience, much more often

- the person does not have the best memory, but loves to talk

- the person has a tendency to "hallucinate" (i.e. has some mild (typically harmless) schizophrenic traits)