I read that, but I'd rather it didn't collapse at all. Or even if it did, I'd like there to have been some way of knowing it was coming. That looks as though you were quite close to being taken by surprise, and it could have been nasty, even without the tyre blowing off. It would have failed under stress, which means most likely on a fast rocky downhill.
Thankfully it wasn't my rim. It came in as a donation to a bike recycling charity I help out at, and I cut it to use as a teaching aid for volunteer mechanics