Pleasance Dome, EdinburghStarting out with a deliciously bumptious persona, Doherty's show trips itself up with a subplot about arts funding Gay Witch Sex Cult was quite the solo debut last year from Andrew Doherty, a folk-horror pastiche delivered in character as deluded estate agent Kaelan Trough. His follow-up attempts something similar, but trips itself up with a split satirical focus. Sad Gay Aids Play starts ou…