OH, I'd like to understand why Paulo made that statement concerning blue water capability of catamarans?
Fast Forward to the present and Catalac 12Ms which are now close to 30 years old are still making Atlantic crossings (S/V Angel Louise - Florida to England via Bermuda and the Azores) or even the lightly built Gemini Catamarans who travel from California to Fiji (S/V "Tere Hau Nui"), none of these boats was larger than 40'. We haven't even scratched the surface yet. All of which lead me to believe that Paulo might have to check the dates on his books as his library might be full of pre 1980 books on sailing.
Things have changed.
I have not said that catamarans were not blue water boats. I said that size by size mono-hulls were more seaworthy and I am talking generically not referring any specific model.
Many monohulls smaller than 35 ft have circumnavigated and even one with less than 24ft had done that without stopping. That does not lead me to say that a 34ft mono-hull are indicated as a voyage boat or passage making (in what regards seaworthiness) even if obviously many had done that.
CE rating is over-rated and mono biased.
The theoretical work where that legislation is based was done by a huge team that included many of best European architects and even at least a well known American one. I have heard the EC ratings being accused of being too embracing in what regards category A boats (no limits) never heard anybody complaining that it was too severe regards the boats that did not reach the requirements for being considered class A.
There are good technical reasons regarding safety and stability that allows some 30ft mono-hulls to be class A boats and prevents 30ft catamarans to do the same.
Note that there is nothing that says that a 30ft monohull or multihull cannot be Class A boats. For being a class A the boat has to pass some stability and safety requirements. Simply what happens is that some monohulls can meet those conditions and to my knowledge, no 30ft catamaran has done that.
We can argue that the theoretical support for those rules is wrong, even if I never heard nobody complaining that it is too harsh regarding monohulls or multihulls, but what leaves no doubt is that the ones that made that rules were among the best specialists in Naval Architecture and knew and know much more than you or I over the subject.