I can't speak on K's behalf, but as a fellow Answerbank user I can certainly speak up for him a bit. He certainly doesn't get all his answers from AB: he's one of that forum's most consistent and longstanding givers of hints, advice, encouragement and solutions. And when he makes a mistake, he readily apologises, in my experience.
With respect, you're missing the point here. It's not that Paul McKenna's puzzles are too hard, it's that many of the clues are so obscure and, on occasion, poorly constructed, that they frustrate even advanced solvers.
They haven't always been like this - up to a few months ago, I'd get through one of P McK's offerings with an acceptable and usually enjoyable level of mental gymnastics.
Now, I can hardly be bothered. I don't have two days to spare, and I hate completing any puzzle with the nagging doubt that I've construed a clue incorrectly or that I've arrived at a solution without certainty as to how I got there.
To use a golfing analogy, it's rather like players hitting their tee shots on a par 3 to within feet of the pin, only to find their ball rolling back down the lightning-fast green into a lake.
There are fair tests of ability, and blatantly unfair ones.