Crossings held out, and how far along the walk each method put the nearest scan from them:
  crossing                            by movement   by clock
  Rivera y Brito del Pino                    27 m       17 m
  Rivera y Simón Bolívar                      7 m       13 m  <-

  mean error: 17 m by movement, 15 m by clock
  The clock wins by 2 m: keep --pace clock on this route.
