Super glad you are unscathed. Wow.  Could it be possible that a small,  unnoticed chip or nick occurred at the edge of the windshield,or within a mounting hole, and a crack propagated from the damage? A rock or other jetsam, or even a packaging, storage or handling mishap?  A materials scientist could look at the windscreen under a microscope and, within a few minutes, tell you where and why it cracked.  Hang onto it, perhaps someone would be interested in doing the analysis.  To be honest, the failure is statistically remote and I would not be afraid to put on a replacement...unless you have been struck by lightening thrice and paid for your Rocket with Lottery winnings
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