RE: We spend so much time ensuring that the props......
Bill,
Thanks for pointing me to that thread on spinner balancing.
I had never really given doing it much thought until yesterday, as having spent quite some time balancing a 12" new prop and then carving a plastic spinner cone to fit the prop, that the thought of it hit me.
Flyboy Dave's comments and picture illustrations in that thread takes all the mystery out of balancing spinners, and are very clear and straight forward.