hang on, it wasn't the foiling jibe issue for not using a soft sail. It was the sheet loads on a soft sail vs a wing. the wing is trimmed by 1 guy on a winch, giving a very quick response time. They would be luffing along/or pinching in the gusts, or going over because the main didn't let out fast enough.
The boats are too active for the soft sails in strong wind due to the crazy high main sheet load on a regular boom and the time it would take to ease and trim .