I think the important thing is that from the blade root about 1/3 of the way to the tip, the paddle with have a soft diamond shape. Through the second 1/3 towards the tip, that diamond flattens out into what becomes the final 1/3 to the tip, which is a lenticular shape. It's not really an oval, it's more of a lens shape, or shaped like a very skinny football in profile. I believe it is this lenticular shape which gives the GP it's ability to wing through the water, and to find a climbing angle on it's own, say during sculling or rolling. The finer the edges of the paddle, the more "bite" it will have in the water, but then the harder on your hands when performing extended paddle positions. I would definitely stay away from a dead flat blade profile.

Brian

: Of course, if the edges were sharper, the thickness of the tip
: looks good, and would form the requisite convex shape. The most
: concise instructions on carving GPs I've ever seen are about 3/4
: of the way down one of Brian Schulz's page here, where he
: illustrates a sharp oval versus a diamond:
: http://www.capefalconkayak.com/northcarolina.html

: It's not *quite* all you need to know, but it goes a long way.