Layline — tack on it, don't overstand

Tacking on the layline lays the mark; tacking late overstands and sails extra distance.

Both boats beat to the windward mark and come in on starboard — the standard tack for rounding a top mark to port (counter-clockwise). Green tacks right onto the starboard layline and lays it. Red tacks late — past the layline — so it overstands, sailing extra distance and arriving wide and behind. Watch the laylines (dashed lines off the mark): convert onto the layline exactly, not beyond it. Turn the wind and the laylines — and the right tack time — move with it.