The Theory is....
Rail dust is the main reason peeps should not let the dealer prep their vehicle unless the dealer follows the proper methods for removing rail dust. If not properly removed your clear coat will become compromised and result in possible severe swirls.
Now i've heard the first step is to use a cascade of water as opposed to a "blast" from the hose...followed by a quality wash mit soaping (heavily and often rinsed between wiping).....and then clay bar....then wax of your choice!
