What made Pilot Cutter so fast? Just rumors?

[NewAlexandria]

I"m looking at WestSail32 let's say, and I'm looking at Pilot Cutters from Bristal, and I don't see the speed difference in the design. It's basically the same boat. Physicals can't be overcome. There is optimal design for everything and anything close to it, will also be close to it in speed let's say. So how come WestSail32 is known for being slow and Pilot Cutters are known to be super fast. I don't buy it. The only difference is the rigging, but in that case most designers would simply select Gaff setup. What am I missing here?