Yes, thanks Nick. I know about using the current grib files but on a closed course, well, a forcast is a forcast. I looked into EXP today and can't find the hold current feature. Is set/drift always factored in for layline calculations or do you have to turn it on? Just asking because laylines from mark and boat always seem to intersect at the same angles on both sides and I've had EXP say it's time to tack when I knew we had to go a couple of boatlengths to make it due to set.
Again, I just try to keep the boat out of the corners and let the crew use their heads for the final approach to the mark.