1. NOBODY is as accurate at hand foiling a fin as a CNC machine.
2. Tiny differences in foil shape can make a huge difference to performance.
OTOH
1. Even theoretically bad foil shapes can sometimes do what you want from them.
2. Sometimes, close enough is good enough, for some people.
Having said that; that is a great job Pepe.

That is also one very nice base mould!