When the wind or tide is pushing a yacht away from the pontoon, the best approach to preparing to cast off is to replace the mooring lines that will be cast off last, with slip lines.
If this is done with a second rope. This second rope can be rigged whilst it is not under load, then tensioned and the original mooring line removed.
This approach will avoid the situation of the yacht pulling away from the pontoon because the person adjusting the ropes can not hold it against the strength of a sudden gust of wind.
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