I would like to confirm the legality of having shock cord run through the clew cringe and forwards toward the mast.
Under rule C6.1.3M sailors are allowed to use shock cord to retract or remove slack from control lines. However this shock cord achieves this by moving the clew of the sail along the boom. The rule does not state that shock cord is allowed to aid changing the shape of the sail.
I have always assumed this shock cord to be illegal as its primary function is to aid release of the outhaul to change sail shape, not to remove slack in a control line. However more boats appear to be using the system which is why I am seeking clarification.