I think that a lot of the info you are finding is relative to the monohull type sailcraft. A genoa is a foresail that is larger than the jib (which is only as big as the area between the mast and the forestay). A genoa overlaps the mainsail and is numbered by the amount of overlap ie: 130%. The spin pole you refer to has the release on the ends because they use the pole on the spinnaker sheets. The hook is attached to alternating sheets as they jibe the boat. The pole on the catamaran is used for a different function because a cat doesn't have a fixed point up front on the centerline.