New series 1/3. Timing Is Everything. One of music's most celebrated observers explains why he can't helpfallingin love. Nik Cohn 's conversion to rock 'n' roll happened when he was a schoolboy in the 1950s. Before long he was at the centre of the storm, reporting on the sights and sounds of swinging London. Producer Owen McFadden Repeated on Saturday at 7.45pm Still hooked on the streets: page 123