Concrete-hulled boats have been around since 1848 and are more common than you might think. I learned that while riding out a storm at anchor in harbour when a 60-foot concrete hulk broke free from its mooring and headed straight for my little skylark with a force 9 wind behind it. I never got a motor started faster in my life.
I rather like Mr Hayes's idea because it takes the heavy ferroconcrete hull to its logical conclusion–even if the hull speed is a bit hard to believe. Perfect for freight companies, rich eccentric with a Captain Nemo fixation, and Columbian drug runners looking to expand.