What are you looking for in a blade?
-Speed & power? Wing blades.
-Utility, ease of maintenance, high-wind conditions? Greenland.
-General use? Average touring blade.
How tall are you? What's your boat width? Where do you paddle?
How long? How reliable the blade is to be?
This list can go on and on...
No single blade can do it all and that's why committed kayakers usually have multiple.
When all else fails you can paddle the boat with your hands and still move at reasonable clip :-)

: Does anyone have a good technical design paper on paddle blade design?

: I have been through the archives, over the Google-net and past a dozen
: pay-per-view sport science articles.

: This isn't a new science, there must exist a decent design primer for paddle
: blades.

: It seems like the two most common methods for designing a paddle blade are:
: 1. Copy an existing blade by making a mold of you favorite blade,
: 2. Custom make one that looks like what current paddle blades look like in
: the store.

: Maybe I am a bit too concerned, but if I am going to make a paddle and then
: us it for a 1/2 a million strokes (not all at once...) then I would like
: to not wonder during all that seat time "how much further would I be
: if I had designed an efficient blade into this???"

: Thanks, Tim