Any single bolt hub can slip if not tightened enough. I had an experience the other day where I installed a wood prop and thought I had it tight enough. When the engine fired the first time, it kicked back and I heard a distinct CLACK sound from the motor. Immediate inspection indicated the prop had indeed slipped and was resting against the cutout in the spinner. I took the cone off and re-tightened the nut, and it neverslipped again.

It CAN happen, especially if you do not get physical with the bolt. All that is preventing the prop from slipping is friction against the backplate for the spinner, which is not that great of a grabbing surface. An approch I have used extensively lately involves drilling the spinner backplate for the small 3W patter, using 2 holes to rest on the anti-rotation pins on the BME hub, and countersinking the otehr four holes on the back of the backplate, then literally screwing the prop down on the backplate using 1" x #10 fine thread screws. The heads fit into the countersunk area very well, and when the entire "piece" is bolted onto the front of the engine, and the holes engage on the anti-rotation pins, NOTHING moves!!!. I make SURE the center nut is as tight as possible, even after this little "fix", though, just to make sure. It's as solid as any 6-bolt setup out there when done this way.