Drills are a good start, and we do them on my boat regularly - at night and durring moderate conditions.
But 30 foot waves 100s of miles out?
Just turning a boat around is very dangerous and difficult, especially if you are headed downwind.
Then there is the whole victim recovery problem:
Again, helmets would be a huge assest for both victim and rescuer:
Note: The SAR pros wear helmets, and with good reason:
Say you manage to reach your victim and it's force 8, at night.
They are concious, but have no helmet.
What are the head
injury risks associated with manuvering a 20,000lb vessle next to them in a seaway?
What are the risks to the rescuer?
One reason Kayakers can survive in whitewater full of rocks - in conditions that make waves from a hurricane
at sea look tame, is because of those helmets.
Thier vests prevent thoratic trauma (broken ribs, punctured lungs, damaged organs) by cushioning impacts.
Look on YouTube at some of the VOLVO
and BOC Southern Ocean footage:
Watch as those poor crew struggle with huge boarding seas and fouled sails
Note how harnesses and tethers are used, and note how they'd be safer still with helmets.
Very few trauma centers staffed with brain surgeons in the southern ocean.
I'm not saying you must be clipped in PFDed up and helmeted at all times -
But setting a wind
speed and sea-state trigger for thier use seems prudent to me.
It's fairly easy to find and recover a MOB in flat water
durring the day.
But at night or in rough weather
So, 30 knots plus, and me and my crew will don kayaking vests and helmets.
We will clip in with climbing harnesses with short double tethers that prevent going overboard
And we will have fun while we are at it, instead of wondering if the next wave has our name on it.