In article . com,
Bart wrote:
Rigging a preventer to a winch that can be eased
quickly is essential. I don't hold to the theory that
it must be rigged from the end of the boom all the way
to the bow. I take it from the main sheet bail on
the boom to a bail or cleat on deck somewhere
around the shrouds and back to a winch.

A boom brake serves the purpose of preventing
potentially fatal injuries caused by a madly swinging
boom without the risk of forgetting to ease the
preventer. A good sailor might be able to put his
tiller down fast enough to slow the gybe, but one
moments distraction might be fatal to a crew
member.

Many vangs can be removed from the foot of mast and attached to the toerail. Works great.