I'm not clear on the defininitions of "cupped" and "spooned". Is a cupped blade curved in one plane, and a spooned blade curved in two planes?

The arguements for asymetrical blades make sense if you are pulling as the paddle enters the water, but I think this is bad practice. I've noticed flutter, and high noise when I do this. Both seem to be a function of air getting into the low pressure area behind the blade. It seems better to plant the blade and then pull.

I have a (symetrical) greenland paddle that seems much more stable when sculling than a blade with a curved face. Perhaps this has more to do with the narrow blade.