Heavy weather sailing
With all due respect, that is actually a pretty poor suggestion. When you ease the vang and pull up on the topping lift you put a lot of twist into the sail, and power it up. That is exactly what you don''t want in high winds because that means that part of the sail will be overtrimmed and part of the sail is undertrimmed. The overtrimmed and powered up portion of the sail induces a lot of heel without producing much drive and the under trimmed portion of the sail is free to flog which really takes a toll on the life span of the sail. A much better stategy that actually does work in real heavy conditions is to tension the halyard, outhaul, mainsheet and vang to really flatten the sail. Then lower the traveller close to its stops to adjust the sail to a small angle of attack. This will reduce heeling and weather helm.