How can anyone tell what is being done on internal side of the glass?
Take a look at HTC latest lamination of "liquid metal finish" paint job on the internal side.
Strong and elastic material like BMG laminate to glass will actually increase the odd of cracking the glass. It will reflect all the force right back to the glass itself. Note all the drop test with corning glass. With the same glass for front and back and identical bumper reinforcement. Unlike the black glass, the front glass never cracked.