What an interesting topic. Myself and my son crewed a 48ft Swan (16tonnes)from Main to Antigua via Bermuda about four years ago and I found myself thinking of how my Bavaria 34 would stand up to such a passage. We left Camden in Snow in November and had a good passage daysailing to Newport where we were storm bound in 55 knot winds. The pontoons in the marina broke up and we were down to the last of our mooring lines tied to the piles before the storm blew itself out. There was a lot of damage, the worst conditions I have ever known in a marina.
About 24 hours after crossing the Gulf Stream we had 55 knot winds which lasted all night and through the following day. The boat felt very secure under a small working jib, set on the inner forstay with the main lashed down. We set the boat up ready before the conditions deteriorated thanks to the owner reading the signs of gales on the way in good time.
It continued to blow hard all the way to Bermuda and we had to wait about a week before we had fair conditions to continue to Antigua. The conditions were so good you could have completed the trip in a dinghy.
I don’t think that my boat in standard form would be up to the job, but it could be modified to complete the passage. Firstly I would modify the companionway washboards and sliding hatch to conform to RORC regulations to prevent water entering during a knock down. I would take a good look at the rudder stock, particularly where it leaves the rudder and decide if it is up to the job or can it be strengthened. I would not set out without my autopilot, which fixes direct to the rudder stock, not the rubber belt on the wheel. I would fit an inner forstay and storm jib and fit an additional track low on the mast to set a tri-sail, without having to take off the main. I would look hard at the opening windows, hatches and through hull ports to assess their ability to remain intact in an Atlantic gale.
With the boat set up ready to go the main consideration is how fit am I and the crew to undertake what could be a very uncomfortable and at times worrying passage and i would not go unless I could trust them all with my life.