We did a capsize test last year - but not voluntarily. There is a report on my blog at
https://www.konfido.info/pocketship/gekentert/, but in German. Here in a nutshell: The cause was a mixture of carelessness, natural conditions caused by a sudden huge gust in a jet and far too little weight in the boat. Important to know: Nothing happened, it was almost fun and the water was warm.
The boat was in the water up to the mast, the sails were slightly under water, the hull floated completely on its side and very high up. Not a drop of water got into the cabin or the cockpit. As some of the water flowed off the sails, the boat righted itself in less than a minute. With more weight in the bilge, the boat probably wouldn't have capsized at all and would have righted itself immediately.
If you get knocked over by a wave somewhere, you probably have completely different problems. But on inland waters, it was a harmless affair.
I may be wrong. My impression is that if you have enough weight on the keel, you're more likely to fall out of the boat when it's leaning than to tip it over.
Damage: Wind vane floated away and tree fitting bent. Mobile phone gone, glasses gone. Otherwise all healthy.
There is nothing good unless you do it.