In case it helps: I read somewhere that the Mitchell version was written in response to hearing a BBC presenter trying to discuss the original without acknowledging that Larkin wrote "fuck". In other words, it's saccharine, but it's deliberately so because it's an attempt to mock the bowdlerisers. Take away that context, though, and yes, it's enraging. And the Duffy is excellent, in a creepy sort of way. Fuck all gaslighters.