Given an undercrewed boat that has significant time to tack and accelerate, and is not terribly weatherly at best, but rates PHRF same as J-24's  (aka Bermuda 40 Classic Yawl) I would like to try to develop tacking calculation for when there is a shift that follows pattern of oscillations, and you are close enough to the layline that you need to decide to squint and ride it out, or tack immediately. 

I'm envisioning a calculation of the time to layline & mark (and likely time remaining before next shift) under scenarios of:
constant heading (foot/pinch as needed to hold course, complex with variable leeway while pinching) 
constant TWA variable heading  (sail the yarns into the lift and go where you go ) 
modulated TWA & Heading ("Wally"?) to pick a compromise AWA and Heading for optimized VMCLayline 

I am assuming the Heel polars will predict heel and with classic polars, thus predict leeway for TWA @TWS?
Could I set up the three scenarios as constantly running, or event (detect shift as TWD <> AVE TWD+/- 5 deg) driven popups? 
regards
S