A few of these very large catamarans have turned up on the river in recent years, they seem to be around 50 to 60 feet in length.
The accommodation and space aboard must be phenomenal, almost as much as the windage. Comparison with the masts of the adjacent yachts which are mostly 35 to 40 footers shows just how high that fly bridge is, great views but not sure I'd want to be up there in a gale.
The pursuit of luxury and technical innovation is understandable, but sometimes there's a feeling that problems and unforeseen consequences are perhaps being designed in.