It's A MastHead Rig ...
You might want to do your own research about my comments below, and also a good source of information is this website's Expert Forum on Sail Trim by Don Guillette.
The Hunter Cherubini 33 (and my 36 version) have masthead rigged jibs; that is the head of the jib is right near the top of the mast. The other main type of configuration is a fractional rig where the top of the jib is somewhat below the top of the mast, say 70/80% of the mast height. On these boats, the mast is located further forward than for a masthead rig and the mainsail is generally larger as a ratio to jib size than for masthead boats. The mainsail on a fractional rigged boat is the primary driver of the boat. If one is to sail with only one sail, my understanding (and from a little bit of experience) is that its the mainsail.
For a masthead rig, the mast is located further aft. The jib has a larger size ratio compared to the mainsail than for fractionally rigged boats. The foresail is the primary "engine" (Don Guillette's description) rather than the mainsail when going to wind.
When I am out with people who are a bit skittish of healing, or if I just want an easier time of it, its the jib that I use. I see the jib only configuration a lot with other masthead boats on SF Bay. If the wind is piping, I think that I'm not loosing much with the jib only. The boat does well with the wind anything forward of the beam... slower with the wind aft of the beam. For the few times I've hoisted only the mainsail, its as you describe -- really sluggish and non-responsive when trying to go to wind. Dismal performance actually. The mast is further aft than for a fractional boat, so weather helm is also an issue.
As Steve Dion queried, do you have your jib on a roller furling? Unless you have a genoa that can't be furled, sailing your boat with your jib only in 25kts should be OK. My boat has a 95% jib. For jib only, I have no problems with it fully unfurled at 20-25kts.
Once when the US weather service changed their initial gale wind warning instead to "5-15 kts", I went out. Before it was time to raise the sails, the wind began to pick up hard. Since I was already out and didn't want to give up on the day (the forecast was for relatively calm winds afterall), I decided to leave my mainsail tied to the boom and I just unfurled my genoa (the headsail I had on at the time) to about 50%. Then I reduced it even more as the wind continued to increase. The boat sailed more or less fine, but the wind kept increasing even more. It was time to get back to my berth; hopefully. Returning to the channel, a number of anchor-outs had broken free and one boat got swamped and was sinking. Actually getting the bow of my boat into the slip was more luck than skill. Getting off the boat, the wind pressure almost pulled the lines and the boat out my hands before I could tie off. Later, I checked the Angel Island wind guage. 59kts was the peak gust for the period I was out. The weather service really botched that day. I later read that quite a few boats got into trouble.
Anybody?
