Jim,
I've always thought the spinner manufacturers should make a design that absorbs energy like the crash bumpers on a car. The inside of the cone would have molded-in seams that would split on impact. The volume of the spinner would be filled with styrofoam or some other lightweight, energy absorbing material. Upon impact the spinner would split open sort of like a a lag bolt used to mount shelves on drywall. It might save a crankshaft.