Hey, I thought maybe I could give you a little inside perspective. I work at a small dealership that sells new and used cars. Just so you know, they base their sales on the relationship with the customer, not fancy this that or the other thing, good deals, or gimmicky radio ads.
Right, on with the show... When I first started working there, I was real hesitant to use their brush. I came to autopia a while before I started working there. I used a wash mitt for everything. Now, I can say that, while it may not be the best for an autopian, it really isn't that bad, especially with a newer head. At least for the tops of vehicles. Today, I did a black Aztek...I did the roof with the brush and the rest w/ a wash mitt. We also wax all the new cars that are sold.
Its all about time. I could spend an entire day doing a car, even a new one. But time is money for them, so I don't really have a problem doing it. People are always happy anyway. To tell you the truth, I'm betting that the vehicles are better cared for by us than most individuals.
We don't do any crazy "acid washes", but the whitewall cleaner is pretty much our "all purpose" cleaner. If there is a really dirty floor mat that needs to be hosed out, it gets whitewall too. The guys there also advised me to use the whitewall cleaner to soften bugs. Really, that doesn't work too bad either. It removes wax, but 99% of the vehicles done there aren't waxed anyway.
The used cars need to be kept clean too. I have no hesitation to do brush washes on them. Even when they come in, the are pretty swirled. OTOH, one of the owners has a black car, and always does brush washes with it. It is pretty scratched or swirled, but I'm thinking hes not the most careful person doing it either. He has better things to do than wash the car. It also rarely gets waxed, so that contributes to the dulling problem.
For Autopians, I invite you to come and do your own vehicle! Where I work, I'm guessing that if you made that request, the would let you come in saturday and do your own car! If your dealer won't let you do that, maybe you're going to the wrong place. I have a feeling that dealers with the attitude of mine are pretty rare, but there are some out there.
a few quick notes:
~time is money
~most people are more than happy w/ my work
~cars come from the factory w/ buffer swirls on occasion...I think that it was probably for a repair of a dust mark from painting, or a scratch
~Repaints and touchups also happen. I saw a car the other day which had been painted on the "a" piller or fender, can't remember. There was overspray pretty bad on the car, it made me sad. I did the best with what I had, using our c/w on the paint, and a razor on the glass. I still felt bad for the people getting it, but they didn't complain, or notice I don't think.
One other thing...when we recieve the cars, some seem to be in great condition, beading water and all, others are heavily coated with either overspray or industrial fall out. I'm thinking it has something to do with how long shipping takes. One recent thing that I saw was a plastic coating on the hood of a Buick. IMO, they should do that on all cars, and more of the body.
Thats it, I'm sure only 1% of the members will read it all anyway.

peace be with you.
Kevin