Patricia Routledge: 'I kept bashing into doors and they kept bashing into me. I got through two bottles of arnica in rehearsals alone'The idea came to me in 1970. I'd written a series of short plays and one night I was watching from the wings, seeing the actors dashing between the different doors backstage. It occurred to me that it was all far funnier from behind than it was in front. But I didn't get round to worki…
