All of the designs have changed where the sails attach directly to the mainsheet block and the boom only acts as an outhaul agent/mast rotator device.
Just a technoid nit to consider that is completely unrelated to the rest of the thread: This (see quote above) is not the case with the VectorWorks Bimare XJ and Nacra A2. On those boats the sail attaches to the boom and the boom attaches to the sheet (the sail does not attach directly to the sheet). I believe they do this so that the sheet and outhaul tension are as decoupled as possible.
