If I remember there was a long letter from one of the Olympic sailors at the trials saying Nacra had broken the mast previously . They thought it should have been tested in the capsize. Knowing Nacra they would have done a lot more testing before the carbon masts were released to the public.
As for the changing to foils again I think some research will show that would be a major change. ISAF which is controlled by all the national authorities of sailing don't do major changes in a 4 year cycle. I remember Tornado wanting changes and it was rejected as it was mis Olympic cycle. After Brazil then there will be changes and then a lot of countries that have invested in a new boat will complain. The idea is not to change boats and equipment to reduce the costs of sailing.
Just a little bit of research shows there seemed to be a problem with Nacra mast even at the trials. That equipment is locked in for 8 years. Though there can be changes after the Olympics.Whether countries will allow the change after investing in a new design would be another question.
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