if you have two abreast, lets assume with startboard side to pontoon, does the line from the outer boat not touch the port tube of the inner boat? Even if the starboard toob has a fairlead on it.
Eye splice on the end of the painter. Second "half" of the line on the pontoon, secured in a fashion to make it impossible to remove. Caribeener spliced on the bitter end to attach to the eye splice. Weight of Caribeener will sink the loose line if its dropped (can be retrieved from pontoon) so it wont float onto a prop.
Painter in the water... ...yip you are right - they will leave it dangling. Were you worried about the impact on fuel economy or that the rope will get wet?
How do you tie the stern off?
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