I think the longer ocean races now require the boat to have an emergency rudder aboard and to have mounted it under non emergency conditions, so more people have been thinking about the subject.
I have been eyeing the bottom of my pilot berth. It is currently made of 1/2 in plywood but if I upgrade it to 3/4 and reinforce it with fiberglass cloth and epoxy it would be solid enough, especially since at least 1/3 of its 6 1/2 foot length would be out of the water. I'd have to get some pretty heavy gudgeons and permanently install them and predrill the rudder for pintles.
It's on the "to do - (eventually)" list.