The evolution of the surfboard was driven by performance.  From wood boards to lighter wood boards, like balsa wood, to foam core.  From heavier foam cores to lighter foam cores, lighter and thinner wood stringers etc.

Take two long boards shaped the same one built to weight 16lbs and the other built to weight 25lbs you'll will find the lighter of the  two to be more maneuverable.

Something that may be over looked in the evolution process aside from boards becoming lighter is the way fins evolved too.

In the early 60's virtually all surfboards had a "D" type fin. And the fin was placed right in the tail. We all found out over time that less fin area made for better performance and well as moving the smaller aspect fin up from tail made for better turning ability.

D.R. 

The above fin was  typical of early 60's designs.

The below fin was one of many more performance fin designs from the mid 60's and later.

The process of designing a surfboard is basically an intuitive process.  For sure there is science behind why surfboards actually work, but the guys that design and shape surfboards aren't scientists... or engineers, at least I don't know any to be.

Wait.... I think Tom Morey may be an engineer, whom I've worked for.

Anyway, as an example, when Blinky got going on his Mega Fish it was an idea he got in his head and tried it out.  At first he messed around with fin placement and changing the rails a little but that's how you do it. Intuitively you get the idea and go after it testing and making changes as you go.

So I've completed the Mega Fish blank Blink gave me and took it for a test drive this past Friday.  I'm not a fish guy... that is I've shape plenty of them but never kept one for myself, until now.  I'll definitely be surfing my new board and working through the particulars. The surf on my first go out was about shoulder high and not real clean but the board worked great. Pretty much as I expected really.

My new years resolution is done.

D.R.