All this back and forth about the rim/tire interface may be important to those engaged in it.
However, I might point out that the OP clearly describes a tire torn from the bead wire. So, the tire DID NOT blow off the rim. It failed structurally due to excess pressure.
__________________
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.