The destination is 3000 mi directly north. The red line is the optimum course (as verified by Zezo router, and by testing in VRTool with multiple track segments). But the weather routing proposes a different route starting with a track that is clearly too high and misses the optimum route altogether. The isochrones suggest that something is cutting off the tracks where the optimum route is.
The settings were:
Boat wake angle: 30
Max angle to destination: 90
Using new pruning method.
Polar: vor0_pro-full.csv (simple)
Changing these settings makes no difference - on the port tack the isochrones are always cut off short.