We've used baby powder on every brakes service, even though no oil had been spilled on any part. For example, new disks and pads, no oil spill, we'd cover each disk with powder and deliver the vehicle that way to the customer, without wiping of the powder off. That way we'd make sure braking was immediate and good, and powder would come off by itself just after few miles.
But, that was 20 years ago, back in days when garage would work much slower, just to make sure vehicle was 100% good after leaving the service. We were under strict control of the one old mechanic... you know, the kind of bloke almost walking arround with a whip... The job had to be done perfectly. Then other times came and our way of doing service was dying. Customers started to look for other places, cheaper and quicker. Our boss didn't want to change, he said he loved what he's chosen to do for living and the garage will keep on providing excellent service for a fair price. I left the shop, took some more education and completely changed my profession, and old bloke watched his garage going out of business. Few years later, he died. Sad story.
Personaly, I hate to take any of my vehicles to the dealer for scheduled servicing, but sometimes I have to because of warranty period. At this moment, I own Glee on warranty and Ford Focus on warranty, as well. I know what they do and how they follow the "checklist" for scheduled service and I have to pay for it. But, that's life.
Sorry, got carried away from the subject. It's just memories of good old garage...