When sailing, I don't dodge pot buoys. My prop shaft comes out of the keel stub (fin keel) and the prop is only about 2" behind the keel. Oriented vertically (the shaft is marked) it disappears. And the rudder has a skeg in front of it. In 25 years with the boat, the 3 times I've snagged something have been under power.
Those folks dragging a 3 blade prop on a strut have a definite issue - pull the shaft right out of the boat! I'm guessing that you have a 3 blade in an aperture, attached rudder.