Most of the time it's not about your answers but about your reaction.

Cool. A random stranger asks you an incredible amount of horribly silly questions in an aggressive/bored/annoyed tone and they expect your reaction to be something else than "WTF? Leave me alone." If this really were about your reaction to questions the staff at border stations would be trained to look for more than "has a beard, looks around nervously" and the questions would be tailored to actually invoke some observable reaction.

Have you had training in what questions to ask in order to properly gauge a person's reaction to said question to determine the likelihood of that person to commit a crime or other undesirable act?

I would imagine in most cases the "WTF? Leave me alone." response would not mark you as anything other than a law-abiding citizen that's just annoyed with the process. They ask the horribly silly questions for a reason. Well, most of the time, sometimes you just get someone who's having a bad day or maybe just an overall jerk high on abusing his authority.

I think tintin is right - your complaint is that it's not effective, which is also probably true. But they just want to get you talking, and your current plans are an easy topic that at least are relevant.