  At the 2005 world championships there was considerable discussion and a
formal protest in the long distance race arising from a perceived advantage
obtained by some athletes running together. It is shown that a statistical
model presented in previous work [1] is applicable to this event, giving
predictions of the final times to with 2-3 minutes. Using the model, we show
that pack formation was inevitable in this format. The statistical benefit
gained at the elite level from running with other competitors appears to derive
both from increase speed through the terrain, and the elimination of large
navigational errors.
