In Praise of Runners
Runners are necessary on a yawl rig at any point when the sail is not hard sheeted as, without them, one has no aft support for the mizzen mast unless the cap stays angle aft, which is unusual as that would limit the range of motion of the sail. This is especially so when the main mast's aft support is a triatic. Without, aft support the mizzen masthead can rotate forward which, in and of itself, may not harm the mizzen mast--but can foul the set of a mizzen staysail--and will allow the main mast to rotate forward as well, making it impossible to trim the yacht's head sails properly as the head stay tension is relieved, causes weather helm; and, results in eccentric loading of the main mast by its intermediate and cap shrouds, which can contribute to a buckling failure of that spar. The multi-part runner tackle allows one to impart rather sizable aft loads to the head of the mizzen mast without a lot of effort and yet, to cast off cleanly, allowing the sail an unimpeded range of motion when the lee runner is not required. The Hyfield lever, with its limited range of motion, does not allow as much "slack" in the lee runner as does a multi-part tackle; and, runners set with pelican hooks may be difficult or impossible to release or reconnect if the mast is heavily loaded by the triatic unless the runners are unnecessarily slack--which defeats their purpose--and, in any case, are certainly inconvenient in comparison with simply casting off the tail of one runner and taking up on the other.
"It is not so much for its beauty that the sea makes a claim upon men's hearts, as for that subtle something, that quality of air, that emanation from the waves, that so wonderfully renews a weary spirit."