What's the deal? When we bought our Javelin 14 the previous owner mumbled something about how the boom can rotate on itself at the gooseneck and you can use that to roll the mainsail around the boom. We had no idea what he meant but figured we'd understand later. I still have no idea what that's for. Is it just a way to store the mainsail when docked? I can't believe it can work as a "roller reefing" system since rolling it would encase the mainsheet line and block and also interfere with the boom vang. Any thoughts on this? Is this standard equipment on many small boats? Thanks.