Mizzen on a yawl:
The handling of this sail seems to be a problem that worries many young skippers. No fixed rule can be laid down, it depending largely on the shape of the boat, the position and size of the sails. Generally speaking, with the wind forward or on the beam, the mizzen should be sheeted flatter than the mainsail. How flat, depends upon the effect it has on the steering. If the boat gripes, ease it off; if she is slack-headed, haul it flatter. In beating through a narrow channel work it as you do the jib, but exactly opposite; that is, with the helm a-lee haul in flat; as she pays off ease the sheet. In this way you will help the rudder to bring the boat round. The mizzen sheet should be belayed where the helmsman can readily get at it, so that by working the sheet in combination with the tiller he can control his vessel.