Basic explanation is right, but it does not apply here. Corrosion would be important if the rear fender was bare and exposed. So corrosion of the aluminum will be minimal unless there are some large bare metal zones in contact with the door (and large bare zones are bad enough as it is...  BTW, this principle can lead to much more trouble with the exhaust in road salt country (I shiver when i see a 304SS steel muffler welded to an aluminized pipe)
Marco Tatta
98.5 SE MTX, Duratec
EGR block, fog light
fix, custom shift boot, monsterflow intake, Ecotek valve
Quasi dual cardoctor exhaust.
Hacksaw short shift, Momo race "s" carbon knob, ghetto rear strut bar, 16 inch cougar wheels with 225/50/16 kumho 712s
| 
