I think you have gotten it.

So indeed 90 degrees is safe. And the issue for more adventurous sailors is to learn how much safety can be traded away for improved flow over the mainsail. Nobody knows yet where exactly the threshold is. That is with respect to the rotation/windstrength combo. Some of us, however, have learned that there is some leeway in trading off safety to performance, the superwing mast seems to be able to take some abuse. But we need still need to be very clear about that this experimentation is risky business.

Wouter