In Light Thickens, the protagonist is described as “walking in ¾ time” or waltz time. But Kate isn’t just walking, she’s skimming along “up to tempo” – as in moving rapidly.
Some people might think a waltz is a slow dance, but we’re talking The Sleeping Beauty Waltz here, where the conductor marks only the first beat of each measure because trying to mark all three beats would have his hands waving like those of a camper caught in the middle of a mosquito swarm.
So why does Kate walk in three-four time? (Three steps to every measure, the first beat of each measure marked by a longer stride. ) First there’s the thematic element, adding to the number of references to the number three included in the story. It also indicates Kate walks to a different drummer, a little out of step with the people around her. That makes the action character development.
The real reason, however, is I discovered long ago it’s an efficient way to walk fast, since I have a slight limb-length discrepancy. If I don’t walk in three-four time, the left stride is always shorter than the other, and over distance I veer to the left. Concentrating on making the left stride longer is fatiguing and wears on the joints. (Fighting the tendency to veer sometimes made me so tense it seemed I was forgetting how to walk at all.)
But when one walks in three-four time, the longer stride on the first beat of each measure alternates between left and the right, and the muscles are worked equally. It’s a fluid way of moving fast, especially if you hum a waltz on the way.