Tough break Loz. Presume you stayed upright or was it just a case of "it don't sound right"?
Woodruff key - its the little chock which fits into a slot on a shaft in order to keep a cog in place on the shaft. IF there's enough force on a cog and enough resistance on the shaft, then I guess the woodruff can be sheared. But it's gotta be one helluva big force to do it.
I'd've said the woodruff shearing is the secondary problem. First one being what stopped the shaft/cog from turning?
Best of luck mate.
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