I'm thinking of an extra-comfortable cruising arrangement. If I were to make the main traveler removable and also set up another right where the companionway opens to the cabin (or even just a 'U' bolt), would there be any tech issues around boom fixing point for main sheet?
I wouldn't have thought so, Martin. Certainly not at the boom point. You would probably want to provide some substance to the floor point where it's fixed though, especially if you were to use a U-bolt.
Mine came with tracks running along the cockpit seats which I've found convenient over time, meaning I can move my traveller forwards or back as I wish.
Most Mk4s have differences in the rigs including boom layout.
The current mainsheet attachment near the end of the boom keeps loads within the boom to a minimum.
If you shift the mainsheet forward attaching to the cockpit floor and on the boom above the mainsheet, the mainsheet looses some leverage on the sail plus increases bending moments within the boom and puts vertical forces on the gooseneck which would stress the fittings.
I have seen keel boats sheeting from the coachhouse with booms bent due to the forces and bending caused due to the attachment being in the middle of the boom.
For cruising it could be done but one of the pleasures I have cruising in the Mk4 is the ability to trim everything to my best and sail efficiently. To me a more basic rig would take some of the fun out of sailing.
With a previous boat, I was using an alternate sail and boom. The main sheet attachment point was about 2 feet back from the OEM boom. I just sailed it with the main sheet angling back. I wondered about the main sheet angling back, but it really made no difference. The critical issue is where it attaches to the boom, not so much its angle. Since the vector is not in line with the sail angle, it seems to have no real effect on trim. Ultimately that may be more practical anyway, because it would get it out of the way of the entrance to the cabin.