Tack on shifts? The BET diagram tells you
The BET diagram (Break Even Tacking) is a tool to help you decide whether or not to tack on wind shifts. If the wind shifts are small or short, the shift won’t produce enough gain to make up for your tack loss.
OckamSoft 5 now includes a live BET diagram page that quantifies whether the current wind situation will allow gaining on a tack. If you tack on a header, you lose distance to weather (DLw), but subsequently gain because of the better angle. If the shift dies out before you make back your DLw, the tack was a loser.
The gain or loss is based on the statistics of wind direction. It is not a prediction – it is a likelihood. And the border between win and lose is your entry of how much you think you lose on a tack. This number is NOT a guess; OS5 logs and analyses all your tacks, so you will know what number to enter. See Tack Tracker…
Bottom line, treat the BET gain/loss prediction as a suggestion, not a guarantee.
If you aren’t sure you should tack, you should consider Wallying. The Wally is a technique for extracting gain from wind shifts without tacking and therefore incurring a penalty. In fact, you should ALWAYS Wally. And tack as well if the BET says its a good idea.