At the Nordic Sprint Championships Simone Niggli was leading by a minute at control 8, but then missed no. 9 as she did not see it on the map. She discovered her mistake at 13, went back and repunched 9-13 and finished the course, even though she had lost 4 minutes and must have known she would be well down the field. She's a great example to juniors, as I know many other elites would just have given up.
See the story at
http://news.worldofo.com/2007/05/03/splitsbrowser-...