A slight thread creep but I hope still relevant. In the early sixties I was an extra in a film called The Wonderful World of the Brothers Grimm', shot in Germany. In one scene we were aboard a steam ship, a paddle boat, sailing up the Rhine. I was chatting, between takes, to Karl Boehm who played Jacob Grimm. He was Austrian and I was Scottish and rolled my 'Rs' quite heavily. When we passed the Lorelei he had to say 'Regardles of its name, a rock's a rock' which he did with heavily accented 'Rs', in mockery of myself. The director Henry Levine made him do the take again but this time soften the 'Rs'!