On our 2002 Nacra f18 the camcleat is on the forward beam as well, to prevent the clam catching the spi-halyard during a douse we have a shockcord from the boom with a shackle attached to spi-halyard behind the cleat. The shockcord basically pulls the halyard up so it cannot be catched by the cleat. With tension on the halyard (if the spi is up) the shockcord is not effective and the halyard stays in the cleat

Does this make sense?