My experience of on -course devices relates to many years of a Silva tactical compass in dinghies and keelboats, and more recently of a course setting disc for setting courses as Race Officer. At first, the wot-tac does not seem very different but then the fact that the compass dial reads anti clockwise – and you can read courses from the windward side of your boat – asserts itself and as the device turns with the boat the course to steer is intuitive, and correct!
I have been armchair sailing around triangles, trapezoids and windward/leeward courses and enjoying the immediate course to steer from wot-tac. To get the best from this gizmo one would need a good compass – which most boats from dinghies up now seem to have . One would also rely on good information from the Race Committee and SI’s with respect to course angles and the bearing to the windward mark.
wot-tac will be especially good when a significant wind-shift is encountered and the dial can be reset – even if only approximately. Then the paying tack, or gybe, will be obvious before the turning mark is reached. For me personally, that would be a great help as I can be slow to work out such things in my head when helming under pressure!
Overall, very clever and useful! I will still use a conventional compass rose when laying courses but a wot-tac will be with me when racing my keelboat.