How valid is Marchaj area under the stability curve for catamarans?

I know nothing about the "Wave Rider" capsize in Tasmania. Just had a quick look on Google.

Looking at the wind moment being applied on a righting moment curve either one of two things most likely occurred:

1) The gust was greater than the ability of the vessel to restore itself
2) The crew were asymmetrically situated on the vessel (transversely) and a gust of wind came along in the sudden opposite direction. Being asymmetrically loaded reduces the Rmax in one direction and thus the RM curve is affected and has less ability to right itself than when seated centrally.

Thus without knowing the the strength of the wind and the vessels stability curve and the crew loading at the time of the accident, hard to say.

Obviously the amount of sail area they had up at the time, is a major factor in all the above too.