It might be that W marks without the gunwhale overhang don’t experience this trouble as often. But having a World, I put some effort into resolving it. Here are a couple of remarks:
I have seen the bungee solution on one occasion in a W, and have seen it fail it’s task.
I tried to solve the issue by installing a fully centered mainsheet system:
…and found it works perfectly for gybing, but creates significantly greater mainsheet tension when beating (inspite of increased purchase to 5:1) and so in strong wind makes you tired sooner. With a standard W mainsail, leech gets overtensioned too, curling somewhat to windward.
I tried the bridle in the centre of the boat:
…but have second thoughts about it since it can make moving from back of the boat upfront (or the other way) tricky.
I have come across this solution on the web:
…but feel it’s perversely overengineered ( no wonder it’s a German boat 😈 ). So there goes a less perverse version of the same thing:
…but hey, I want to be able to row the boat. There’s no point in having a W if you can’t row it!
So the quest goes on…. 😀
Here are some silly and yet untried ideas:
a. Install a soft plastic stick (like those used for nylon camping tents construction) from one side of the transom to the other, forming a horizontal semicircle behind the boat (or even better a semiellipsis?, it might be possible to install it by pushing the ends into the rubber D-section fend-off perhaps). The mainsheet might be fooled into thinking that we have a round stern now, and thus give up looking for the corner to catch).
b. Install a bridle as suggested – a little forward of the transom, perhaps at the level of the bulkhead. Then install some kind of short slightly bendy flag poles on either side of the boat, a little behind the bridle attachments. These should stop the mainsheet from sliding along the gunwhale to the rear corner, but will surely look crazy and possibly cause some even worse and at this moment unpredictable troubles.
And to end this useless post with another interesting picture:
It’s the stern of a Bristol channel pilot cutter (probably the most seaworthy sailing vessel of all times). Through the above headaches I have developed a deep appreciation for boats (pardon me, it is a ship in this case isn’t it?) with a round stern. But can you spot the metal spring? And you thought that bendy flag poles were a strange idea…
Best wishes
m