For many of us, our memories of great performances and extraordinary productions are infinitely precious. I can still vividly recall Sir John Gielgud using that wonderful voice to illuminate a whole range of Shakespeare’s characters for his “Ages of Man” one-man show at the Theatre Royal in 1963; or ten years earlier Anthony Quayle centre-stage at the Tivoli electrifying us (and, I have been told, terrifying his fellow actors) in Othello’s “Farewell the tranquil mind” speech. But on both these occasions I was privileged to have good seats and Gielgud and Quayle were determined to give their best at every…