Originally Posted by WRXHillClimb
If only such a surface was actually rigid and didn't flake or chip at the SIGHT of a rock and could stand up to abuse without rigorous maintenance and didn't fade etc.
It's like you think no modern cars rust from regular driving on salted roads any more because they all have paint? Rust is like cancer: starts in ONE microscopic area and spreads like wildfire.
There are other corrosion protective measures that bond to the surface chemically (flex and don't flake off) and do cut the corrosion potential back to the same levels as previous materials. These chemical treatments have been in use for a whle.
GM has a 6 year/100,000 mile corrosion warranty, they aren't going to screw themselves by putting rust-prone materials on cars.