It makes me sad. Derek is fun, a great entertainer. I love his work, but...but...but...
What is the psychology of the fraudulent medium? Do these guys start off with a gift of sorts which they then betray as they climb the ladder and put themselves in places where they have to perform to order and under pressure? Or are they bare-arsed fraudsters from the start? I used to read tarot once- I sort of knew what I was doing- but I wound up pushing my ability further than it would go and- anxious about what was happening to me- got out before I freewheeled into the ditch. These days I won't touch the cards. The fields of the occult and the paranormal aren't evil in themselves, but it's right there should be warning signs posted at the gates. You can be an ethical occult practitioner or medium, just as you can be an ethical politician or advertising executive, but there are chances for corruption at every turn.
I knew a chap once who had carved himself a niche on the northern/midlands occult scene. He knew all the players; all the players knew him. He was clubbable, outgoing, charming, roly-poly and a complete fake. Test him on any of his many claimed areas of wizardly expertise and it was like pushing a stick through wet cardboard. I concluded, kindly, that he was a fantasist, a Walter Mitty- and since he wasn't making money out of his activities we'll let the judgement stand.
Another thing I figured was that he was cunning but not very bright.
But the people who do make money out of their non-existent or overstretched gifts- how do they sleep at nights?