from reddit: if your snowblower gets tangled/stalled, remove the spark plug to clear compression from the engine. There is potential that when you clear the obstruction the compression could turn the engine over sufficiently to maul your hands!
seemed advice worth sharing. even if the probability is low, the outcome could be catastrophic (said like the problem manager I am)
Hey if this ever happens to you and you stall out your blower go ahead and pull the spark plugs to take compression off the engine. My step-dad was clearing a snow blower of a string of lights and as he cut away the wire the engine still had compression and the auger rotated rapidly even the engine was off and his hand got caught which quickly broke his wrist.