Knowing why and how is always best however, sometimes not really necessary. Provided you validate your models and metrics you can come up with say version A x version B and choose the one with the best results.
The hardest part is to validate your models specially when there are lots of variables which are evalueted subjectively. One can say in which area a new board is better but cannot objectively measure it.....(yet). The task and job would be really huge but it has been done in other engineering areas.
Simulation programs are target to reduce the number of prototypes required to check a new design.
As far as I know the windsurfing industry has been improving its products through massive experimentation. Sometimes trying things that shouldn't work but that end up working in a different hull, for instance.
Working with simulation would in time reduce experimentation a lot and therefore the money spent in so many prototypes.
Example: in the auto industry a few years back sometimes one would have to actually crash 10,15 even more prototypes to get the desired results. Nowadays they crash only 1,2 to confirm simulation.
Hopefully all the money saved would mean cheaper products .....maybe