Per (PeteCresswell):
Should I resign myself to changing back to feathered if I get a solid-shaft
paddle?

Oops, just read a reasonable-sounding argument for 90-degree feather in a surf
paddle.

The spiel is that when you're punching through a wave with one blade in the
water and driving, the other blade (the one that gets hit by the face of the
wave) meets the wave edge-first.
--
PeteCresswell