I sometimes go out single-handed. I have a single bow warp that I run back to the cockpit so it is to hand when I need it in a lock. It tended to get caught under the overhanging parts of the tunnel light and water heater flue, so I made a very simple modification using some strips of thin aluminium.

These are simply shaped to cover the overhangs. Strips of adhesive velcro secure the aluminium along the tops and where they meet the roof of the boat. When they are fitted, the warp easily can be flicked over the obstructions and no longer gets caught beneath them.

(Many thanks to Andy for his kind permssion to include his © photos and text on this site)