comparing rudder strength
It has been observed that a stand alone skeg or balanced rudder has enormous forces acting on it that a keel hung rudder doesn't experience.
Trying to remember, but the rudders mentioned on this site don't talk much if at all about the wood falling off - it is about metal: the shoe has a number of issues, corrosion at the bolt connection of the planks to the shaft, the shaft corroding up in the tube, the shaft wearing out the bearing at the tiller head. The original rudder engineering seems to have done just fine for four decades. Right?
The keel hung rudder is exactly where a rudder should be. Protected, very little stress on the blade, less force needed to steer. Can't back the boat up so good. tho.