On Mon, 26 Dec 2005 19:55:05 -0500, "Eisboch" wrote:

Worked fine for 1500 miles to Florida. So what am I missing?

Nothing, that's the way most folks do it. The GPS displays COG
(Course Over Ground) which is the combined effect of Boat Speed
through the water, Heading, Current Speed and Current Direction, plus
any set due to a crosswind. It is impossible to separate the various
components without having a very sophisticated instrumentation system
such as the ones that many racing sailboats carry.

If you set both a "From" waypoint (sometimes done automatically), and
a "To" waypoint (destination), then the GPS can also calculate XTE
(CrossTrack Error). Most GPS units today can direct the autopilot to
minimize XTE and thus maintain a straight course regardless of current
or wind.