I just did.
Found an old pair of Oakleys and a dowel rod...
As you can see by the marks on the lens, I hit this area as hard as I could and it never separated. Even with repeated attempts on hitting it in a downward motion (pictured is straight on), it never came apart.
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Next I hit the top edge straight on and at an angle (shown below), still didn't separate.
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The only way I was able to get it to separate was by hitting it repeatedly at this angle (horizontal to the lens),I was hitting the frame, not the lens. As you can see this resulted in the 'branch' sliding past and being embedded in either your helmet shell or skull.
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With that said, yes it could still happen, we've all seen the crazy stuff that happens at times.
For example if you came down on a
fixed object like so...
View attachment 10404
...
the object stayed in place while you flipped over it...
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...and you ended up like this...
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