I'll toss my 2 cents into the kitty...

I had my windshield replaced about a year ago. Original 1985 windshield had
pitting you wouldn't believe -- if driving into the sunset, it was opaque.
Poor neighborhood kids running and screaming, oncoming cars honking, driving
with my head out the window, etc.  Got a new windshield and the next day, a
small rock put a nice set of 3 gouges right in my line of site.  Not
chips/bullseyes, just gouges.  I've wondered the same thing, is this glass
just softer?  I've taken bigger hits on my old windshield with no marks.  For
that matter, I took a foot-long chunk of truck tire tread square in middle at
highway speed, with no ill effects.

Maybe it is softer.  New regulations?  Cheap glass?  More safe?  I'd like to
hear from a glass engineer what the various differences in glass are.

Bill Marshall
85 GL Tiico "Pandora's Box"
Bradenton FL