| > | But rotating booms might be tough with wishbone booms, why is it hard for the wishbone, or half wishbone to rotate around a fixed mast?
| >
| Because it is usually only attached with a single string, id the mast doesn't rotate, the attachment point on the mast needs to move as the sail does. This can be arranged using a strap, but adds complexity when the sail is raised, reefed and lowered.

I am not sure I understand, but, I am not sure I need to.

Is there more complexity/cost/reduced robustness/failure modes in rotating masts, or rotating booms? And/Or, what do I/We need to know about this to pick a solution for a boat?

If you think it interesting, I would love to know more about how this all works.

Topic change;
Please find attached a Ex40F pic.
This is 8' folded, correct?
What is the approximate width of the Ex40F hulls?