I've used them on ships

*that* of course is exactly the same as a recreational sailboat.

I had one on my 26' Contessa,

yes, of course. that explains all.

which I was
able to use to get some relatively accurate fixes (at least accurate
enough for my needs).

sure, plus or minus 100%, distance. good enough to miss the granite ledges 60
yards away, right?

otn