Around this routine, for some 22 years, the 6ft 5in son of a Rotherhithe docker built a quiet, modest life in different parts of London, mainly south of the river. On his days off or before coming into work for a late shift, he wrote his radio plays, some of which were broadcast on Radio 4.
It is only a slight exaggeration to say that his entire writing life involved radio plays, a medium which, as Samuel Beckett and the pre-television Goons well understood, honours the imagination as no other. Casson had one play performed in a pub theatre but the retinal aspect took away from the absolute simplicity and poetical purity of his aural imaginings.
Casson's plays never had more than three or four characters and usually deployed south London villains, boxers, tipsters and other working-class types. Menace, betrayal, disappointment, grief, communication failure, survival: these were his themes.
In Strawberry and Vanilla, his last play (inexplicably turned down by Radio 4), an old Jewish couple are at the beach on holiday. He sent me this play, a new departure in terms of language register, for comment, and we had an instructive discussion about his use of Yiddish inversions in English. Not until the very end of the play does the old wife admit to her husband that she has cancer.
Casson wrote the play before he discovered his own lung cancer. "The bastard," he called it, and his friends and partner Lesley, a diminutive photographer (mind you, even his six-foot friends were diminutive beside him) were privileged to witness his brave but ultimately unavailing struggle against a heavyweight opponent without gloves.
He was a radio playwright pure and simple. Nor were there any satellite activities such as book reviewing, translation, art criticism, obituaries: nothing but his art, his private life and his day job. Casson was not a journalist in the newsroom. He started out as a typist, and then progressed to shift-leader typist or "clerk", ending up as the newsroom manager, a sergeant-major figure between the service staff and the journalists, and between the journalists and the management.
His performance on the day job was a class act, an art form. Connoisseurs of how to get through the day in an office when you would rather be at home writing plays - observed a man who did his assigned tasks well above the level of competence required but whose every word, every inflection, every movement, was an implicit and entertaining critique of his situation.
He would tease his interlocutor and himself by playing at being himself, by playing himself. In effect this quintessential member of the support staff had the leading role in one of his own plays, with senior journalists and presenters as walk-on parts as well as audience.
Something else, too, was going on: big John was (unconsciously?) rehearsing speech rhythms and reactions, in order to recycle them in his plays. At the same time the consummate manufacturer of highly inflected rhythmic speech could not but deploy his artistic skills in daily life, and in this he had an advantage over newsroom poets, novelists, painters and other "double-lifers" in the pre-Birt newsroom.
Like the painter of Las Meninas in the Prado, Casson was always one move ahead of the cast. If you dared to build an awareness of his behaviour into your reaction he would trump you. If you spotted the trump card the game would continue in the bar and even on the phone after work, a Velasquezian series of reflecting mirrors. Had Casson been real Marrano, he would have outwitted Torquemada.
You couldn't miss the big fellow, painfully thin even in health, a lantern- jawed cheroot-smoking individual who was not particularly happy, but whose life was full of meanings. He had a deep understanding of human foibles, and a brilliant ear for their expression, both in the office and in his real work.
John Casson insisted on entering a hospice in order to give his loved companion a break, and died a few days later.
John Casson, radio playwright and newsroom manager: born London 29 July 1937; married 1960 Gwen Arrenberg (two daughters; marriage dissolved 1983); died London 1 March 1999.