A Vendee Globe for multihulls is a way to say it: the same concept, a solo non stop circumnavigation but raced in multihulls between 24 and 32 meter (78.7ft and 105.0ft). Probably the race is going to be called "Brest World Ultim Tour" and will start on the 29th December, 2019.
No, it is not a crazy idea and there are already five sailors and boats that have confirmed the participation even if one of them,"Actual" sailed by Yves Le Blévec, has been recently pretty much destroyed after a capsize, when he was trying to beat a circumnavigation record. The others are François Gabart (Macif), Armel Le Cléac’h (Banque Populaire), Thomas Coville (Sodebo) and Sébastien Josse (Edmond de Rothschild).
Actual will probably build a new boat for Le Blevec (they said that they don't want to finish their sailing sponsorship over a failure), Sodebo is building a new trimaran for Thomas Coville, so the actual Sodebo will be available for another skipper and Françis Joyon is still deciding if he will race on his old boat Idec Sport (that was recovered after the capsize that killed Guo Chuan).
More probably IDEC or other Sponsor will provide a new boat to Francis Joyon (it would be a shame if the old champion had not a competitive boat) and then there would be at least eight boats on this race. Of course Multi 70's can be modified, made bigger and there is still time for building a new boat till December 2019, allowing more great multihull solo sailors to compete.
And they are not so many able to do this race. It was with some disbelieve that I read on some facebook pages that the circumnavigation solo record by François Gabart had all to do with the boat and little with the sailor. Somebody even suggested a minor sailor could do the same!!! Regarding that, the answer Michel Desjoyeaux gave when he was asked if he would participate on this race is enlightening. The only sailor that won twice the Vendee Globe said (translated):
He replies no, that he would not leave on this kind of boat ... " In 2001, when I was with PRB - the sponsor of my monohull -, Jean-Jacques Laurent, the director, had proposed to me: "If the Vendée is done in multihull, I will inscribe you" ... I replied: " No, you will have to look for another skipper ... I did not want to do that on a multihull, for subjective reasons ... and because I have solo sailed multihulls I know that can be done but I know also what it is like to sail solo on a multihull, which is probably the most complicated thing for a sailor. "
On the link below you will find one of the most interesting articles about maxi multihulls and their solo sailors, written by Rémy Fière, one year ago. It is also impressive what has happened in just one year in what regards beaten records.https://www.lequipe.fr/explore/les-nouveaux-monstres/