Logman,
How much rocker is in your 9' 6" ?
I have about 4" in the nose & tail of the 7'10 & 8'2", it seems to work ok.
As soon as the wave is under the board, it is no longer "boggy. But what else would you expect, the shorter we go the worse it will paddle, thats the price we pay. But when on a wave, its a new ball game.
A "spiral V" is a vee that starts from a flat mid area & gets greater toward the tail. If you were to continue that angle off the tail, eventualy it would form a spiral.
It tends to be more appropriate for what we are doing on waves, carving arc's & improves fast changes of direction.
There is quite a bit less paddling resistance between the 14' & 16'5" so you could imagine what the 8'2" is like.