TO VANG OR NOT TO VANG: WITH A PULL or WITHOUT A PULL
Don Lincoln from Brighton:
“Last year I bought a new Dacron mainsail for my 36 foot with full armor.
Unlike the old one, the new mainsail has a free luff.
On my boat, the boom sheet is attached to the middle of the boom and has a traditional (non-rigid) guy line.

My question is, does the boom guy really work?
My subjective opinion is that the boom pull has practically no effect, except that it slightly changes the sail profile, making it a little flatter.
ANSWERS BY BRIAN HANCOK
There are a couple of things to consider.
Do you have a geek sheet on your boat? Or is your sheet secured at a fixed point?

If there is a boom-sheet shoulder strap, then you do not need a boom guy, or at least you do not need it so much, especially when walking in strong winds, since the mainsail can be controlled quite well by observing the leech.

On the other hand, if you have a boom sheet attached to the middle of the boom at a fixed point, then you need a boom guy because it will pull the boom towards the deck, flattening the sail both when sailing in strong winds and when loosening the boom sheet.
Bottom line: you want to be able to control the mainsail as best you can.

But especially you don't want the mainsail twist to increase and the leech to open when the boom slackens.
14.03.2021
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