Lots of opinions here. I refer to the grommets (or cringles) at the reef line as reef points and the lines that go through them as tie downs. I see other definitions above too say I might be incorrect. Never heard of nettles. The proper knot
is the slippery reef. A reef knot
is a square not.
I definitely use them. I don't want a bunch of baggy leftover sail catching the wind
and flapping about. Sometimes it is hard to reach the after tie downs so you have to head
up to center the boom a bit and need to pick your wave and wind
to do it.