From Salt Away: "Salt-Away is used to dissolve and remove salt from any surface. It is water based, non-hazardous and biodegradable. It protects metals from corrosion by removing the salt that promotes corrosion. It also contains rust inhibitors that help protect the surface once the salt has been removed."
A) The presence of salt does increase pH and coupled with soil/etc buildup will corrode a vehicle.
B) The Salt Away is "water based" yet goes on to claim that water will not wash away salt (which it will, salt is a naturally adhesive material). They then claim that while being non-hazardous, it can break down the salt (which is not believable, to break down salt you will need something equally aggressive and therefore likely hazardous and not belonging near your cars finish). They also claim it contains rust inhibitors...which it may, but those will not stay as deposits long before they are too washed away.
C) Your best bet is to wash your car weekly/bi-weekly during winter. Take it to one of those automated car washes that has an underbody rinse. When winter is up (and it has rained enough to wash lingering salt off the roadways) wash your car very well and make sure you get in tight areas where salt/dirt deposits exist and get missed by a quick once-through wash. A good coat of wax before winter will offer a good non-conductive interface between the two and go a long way.
2004 325CI - 2003 3.0 Z4 - 1994 325i - 1967 1602 - 2008 328XI - 2009 135i - 2007 Jeep Wrangler - 2014 *Loading*