To me it is not so obvious? What must a blue water boat have to be classified as such?
I don't think so as we see many boats without that people consider as blue water.
I don't think so as we see many other keels in use with with a blue water tag.
I don't see this as a prerequisite. Medium and light are used in other "blue water" boats.
We see centre cockpits, rear cockpits, wide and narrow cockpits in broad range of vessel that would call themselves blue water.
Don't think this is a limiting factor. We see many ocean crossings on very small boats with limited capacity and of course we have water makers these days.
Rig and sails
Most builders seem to be using a common parts
bin from just two or three main suppliers for booms, furlers, masts and general rigging
so it cant be this.
Seems that primary hull
design and size dictate arrangement.
manufacturers do not make reliable and not so reliable engines.
Hallberg-Rassey's have two big rigging
obstructions midway up the deck you have to limbo around. It cant be this.
, Glass, aluminium, exotics. They are all sinking. Can't be this.
Bespoke and production all comply with the same CE standard for ocean passage
and does a boat have to be slow or heavy or big to qualify as a blue water boat. Me no think so.
Holistic build quality/strength/components/over design?
I would suggest this would be the prime candidate of distinction but how do we measure it? We can't easily and because we can't we rely on our intuition that full keel
and heavy displacement
equals a sea worthy blue water boat. (Baloney) If a yard or designer
wants to sell us a boat based on its "blue water" credentials then surely these merits should be measurable against some kind of standard.