We had 5-7 "accidental" jibes one afternoon when I (as in me) wrapped the spinnaker around the roller furled jib in 25-30 knots. Anyway, I had an excrutiating 30 minutes getting the 2,000 SF chute down. While doing this, for a variety of reasons, we went through a bunch of slam jibes. That happend a decade ago, our rig is still up.

Maybe the way he had a preventer rigged or ????