Am I missing something here?
Can't we just make our own curves, empirically?
One just goes out sailing at various headings and keeps some notes about what sails we're using.
The GPS and a some sort of wind direction recorder keep the speed, boat heading, apparent wind direction, and wind speed notes. It might be a spreadsheet puzzle to pull true wind from apparent, but not impossible.
If you want to see if you're going as fast as possible, then two-boat testing is in order.
The two boats sail next to each other. Same heading, same sails, same hull trim, same ballast. Both boats trim for top speed. Slow boat gets to adjust to try and keep up with faster boat. Once you're both equal, start methodically adjusting settings to see what's faster and what's slower. it just takes time and discipline.
There are plenty of starting points (rigging settings) for the Capri-22 available on line.