Hello!
Are you able to judge the 3nm off track so accurately?
I always wondered (same with the rule of sixty): If people are able to determine their track error with such precision, why did they get off track in the first place?
To me, all these methods seem purely academic anyway, especially in the year 2009 (soon 2010!). I rather train my students during their all-too-short and outrageously expensive (at least in my part of the world) flying lessons in state of the art navigation methods that will enable them to stay on their intended track all the time.
Greetings,
Max