I'm with Wouter on this. And it's not just about spinnaker and non-spinnaker boats. It's more generally about fast boats and slow boats being on the same course. Especially downwind, where various speeds of boats and sail configurations are all sailing different angles downwind -- including some sailing straight downwind. And slow boats may see the collision coming, but they do not have the ability to get out of the way -- sort of like a manatee getting run over by a powerboat.