Cool story. Personally, I've had the sailing habit since the 80's, and have never heard of internal ballast breaking loose from a rollover. Did see one loosened by rocks, though. I wonder if any Ariel has actually been rolled. There is a caution somewhere about the lead pig in the bilge of my engineless boat. Consequently I shimmed it up years ago.
I think we're all better off with internal ballast. People have lost their lives in the past when their bolted on keel just fell off and the boat turned turtle.
Your trip reminds me one I crewed on from Moss Landing to Catalina on a Yankee 28 ( internal ballast). The skipper had lots of Dutch Courage, I was scared sober, so together we made it through.
Thanks for the reminder. Time to read Coles again.