Underway - Pacific Crossing Notes: A Sailor's Guide to the Coconut Milk Run - page 122

Changing the Game
Now that we're no longer bogged down by tedious sight reduction work, we can think
about how to best spend our precious time at twilight. Figure 2 introduces some of the ter-
minology referred to in the text below.
Figure 2: The Intercept Method - some terminology
According to traditional lore, you should have at least three, but preferably four or more,
LOPs from different stars or planets. The more LOPs you have, the better you can box in
your position, or so the argument goes.
That approach works well for seasoned navigators with a few thousand sights under their
belts and with strong confidence in the accuracy of their sights. For recreational practition-
ers, however, taking single sights of many different bodies is perhaps the least effective use
of our limited time at twilight.
For us, the accuracy of each altitude measurement will typically be uncertain. Adding more
measurements of doubtful quality is more likely to increase ambiguity than to improve ac-
curacy (see Figure 3, Plotting a Fix ). Fixing our position inside (and in some cases outside)
the cocked hat ends up being mere guesswork and makes it difficult to systematically
identify and learn from our mistakes.