Just like at the moment, they haven't been able to figure out how to separate a large bottle of explosive liquid, and put it in lots of little bottles which are then allowed through security.

Pretty standard questions to check to see if you are really doing what you say you are doing. Visiting? Business or holiday? Where are you staying? Got enough cash to cover that stay? The best thing to do is pre-book, take a print-out of where you are staying on your itinerary. Just doing their job - looking for travelers not sticking to their plan.

Can be. Not saying that's what they are doing in this instance.

True.

Add demeanor, body language, appearance to these questions. I think there a lot of non-verbal questions being asked by the person looking at visitors. One of the most useful is the ability to read"body language" and fit. Does this person fit the right pattern? Are they hiding something documentation and other procedures missed? Of course this will get a lot of false positives like the parent post.

The other funny airport thing I had was just after the hand baggage restrictions got tightened. I had my hand luggage searched by hand, except I'd packed it so tightly with various gadgets, leads, electronics etc, the guy took one look when he opened it, and you could see his face/expression - "sod that, I'm not packing all that back in". And he closed it right up again.