My car had 36 miles on it when I bought it - and most of those were from when the dealer drove it from the Rockville dealership to the Frederick dealership. I just took it really easy for the first 1,000 miles (never shifting above 3,500 - 4,000 rpm), then drove normally from 1,000 to 3,000 miles. At 3,000 miles on the dot, I switched to synthetic oil. I don't have any experience with freshly rebuilt engines, but that's what I did when I considered mine brand new. I bet the factory probably has a process similar to what you described that they put their brand new engines through before they release them to the dealerships, but that's a complete guess.