Strong language in Larkin is put in not to shock the reader but to define the narrator's personality. When Larkin's narrator in 'A Study of Reading Habits' (in The Whitsun Weddings) said 'Books are a load of crap' there were critics - some of them, incredibly, among his more appreciative - who allowed themselves to believe that Larkin was expressing his own opinion. (Kingsley Amis had the same kind of trouble, perhaps from the same kind of people, when he let Jim Dixon cast aspersions on Mozart.) It should be obvious at long last, however, that the diction describes the speaker.