Stuff will break and fail on a boat, but the integrity of the hull? Common sense to me says a well built ocean going fiberglass hull shouldn't break into big pieces at sea, or even as it gets ground up, to go into a landfill.
That's not hard to achieve in the design or the building. If you compromise the hulls strength for less weight or cost(speed, purchase $), then breaking in half is acceptable but I wouldn't compare it with a correctly built hull.