There is no difference between having a 10 ton whale hitting you at, say, 5 knots and hitting a rock at 5 knots. Actually, the rock is a lot harder and it's connected to a far larger mass. If every ocean going boat falls apart and sinks every time the rudder/skeg/keel hit something, sailing magazines would be like civil aviation mags: listing casualties all the time.

A well designed ocean-going sailboat should survive a blow in the rudder, even if the rudder itself does not. Think about it, we know of two boats that hit tankers and survived without compromise to the boat (that 16 y/o girl, and the 1000 days nutcase^H^H^H^H^H^H^Hguy).

There are details to be know still, but it seems that kind of boat should be limited to coastal sailing. Had they not be so well trained, equipped, and close to the US coast, this will be a very tragic event.