Well, you never can tell. When someone says they've found a novel test for weeding out bad applicants, that sounds interesting. When the test is described with a handwave as an interesting puzzle that the best applicants leap at the chance of solving before reading the rest of the interview.... and then you don't even give us the puzzle, but rather launch back into the HR aspect... well, that just seems cruel. It's like reading a murder mystery where the detective details how he figured out who the murderer is, and then never tells anyone. From my authoritative position as a random anonymous internet jerk, I assert that if you allude to a puzzle, you ought to at least include it.
I am apparently puzzle obsessed today. Slow day at work.