There is utility for sure in digital charts and the ability to set a way point and have the device do some computation "instantly". I use the computational ability of digital charting.
For example if I want to fetch a mark which is 40 miles up the coast from my present position, I can program that mark as a waypoint and see the rhumb line path to that point. I can "see" on my plotter if that path crosses thin water
, or if buoys are in the path, if it cross traffic lanes or area of strong currents and so forth. I could do this with a chart and a straight line. The device does it with a few key presses. It will also compute the time to get there at my present speed over the ground (which is more than likely to change) and it will constantlly up date my time of arrival... which I can do much about and which again is only reliable when I am fairly close to the mark.
I can also use the projected course like to "plan" my tacks if I can't fetch the mark directly which is often the case. The plotter will show me my course made good and I can see where thatis taking me because it has a line showing where I am going to be if I remain on the same course. It also shows me my heading (I have have the compass
connected to the plotter) which reveals the current
and leeway way data . So if the course to the mark is 85° but I am making leeway and there is a cross current
I can set my heading to make the COG match the rhumb line to the mark, if it's one I can fetch without tacking. This applies to motoring in cross currents as well.
The net effect of using these data, is that for distant marks I can sail the shortest course, ie a perfect rhumb line. Of course when there are complex current and eddies and wind
shifts near topography and so forth, the plotter is of less use since these data are not processed by a standard high end plotter. For this you would need more inputs like predicted wind
direction and speed ahead as well as accurate current information.
When you set off on a very long jouney such as CT to Bermuda
you will have to consider the Stream, crossing it and the eddies on either side... and the rhumb line is not always the fastest route. But with some strategy you can still use a waypoint (or series of them) to make your way avoiding the worst conditions and trying to stay with the best. You need good weather
current (Stream) predictions and some sophisticated "what if" programs to see which would be the fastest based on the predicted conditions, which invariably change anyway and so it all is getting updated as you go.
Sure... setting a buch of waypoints to use to motor
at night (or day) along a channel can be handy. I don't know that one needs a capacity of hundreds or thousands of them. Usually you can work with three or four and add a new one as you make one.
I think this route and waypoint thing is way over done.