Gaff vangs are difficult to rig on the aft-most sail, so are typically only found on schooners or ketches, and then only on the foresail or mainsail.
[7] Gunter-rigged boats are similar, smaller vessels on which a spar (commonly, but incorrectly called the gaff) is raised until it is nearly vertical, parallel to the mast and close adjacent to it.
In short-ended craft with full body, heavy displacement and moderate ballast ratio, it is difficult to set enough sail area in the Bermudan rig without a mast of excessive height and a centre of effort (CE) too high for the limited stability of the hull.
[9] Whilst reaching, the CE being set further back, will encourage a small craft to bear up into the wind, i.e. strong weather helm.
[citation needed] The usual adjustments to mast rake, or even bowsprit length may be made to a gaffer with persistent heavy weather (or lee) helm.
Running goose winged with a balloon staysail poled out to windward will balance the CE; Nick Skeates circumnavigated Wylo II with this configuration.