Adding a spinnaker pole
Most cats sail with spinnakers, Wingakers and Parasailors without a spinnaker pole. Without a mainsail this works fine. Very relaxed sailing. However, I don’t like it when I cannot douse the spinnaker behind the mainsail. I tried sailing my symmetrical spinnaker with the mainsail up. Dead down wind this works fine because you can ease the leeward sheet such that the spinnaker moves opposite of the main. For True Wind Angles (TWA) less than 160 degrees there is also no problem. The wind then blows around the mainsail. The problem is a TWA of 170 degrees. The mainsail disturbs the airflow too much and the spinnaker collapses and twists around the forestay.
I have raced mono hulls all my life. Spinnakers are always flown with a spinnaker pole and we never had any issues. So I installed a spinnaker pole on our Saona. I can now leave the mainsail up, giving me an extra knot of speed. The control of the sail is easy now and I can douse it behind the main.