JAX,
Just to get something clear, are you talking about the prop shown under
"Diagram" on the Autoprop website- http://www.autoprop.com/ ?

JAXAshby wrote:
Fact remains, the blades on the autoprop swivel to be inline

a corkscrew surface can not be "inline" with anything except another
corkscrew surface

with the
shaft, and present less drag than in the forward or reverse
direction,
how is that not feathering?