Priming the rebuilt engine question

I was recently talking to someone at a local shop who specializes in muscle cars as they were doing a cars and coffee. They do mostly fords and chevys some mopars. They are also well known in the area for doing great work. I was talking to him about how various things and he brought up how they prime engines that have been rebuilt. He says they crank the engine using the starter - no spark no fuel and watch for the oil to reach the lifters and rockers. I was a little socked by that as I always thought that was not a good idea on a rebuilt motor. But it did get me thinking as I have never thought about priming the motor like that. It certainty seams it would be quicker and easier to do.

What do you al think about priming the oiling system this way.
There are probably a couple of million new OEM motors built every year and I would bet that none of them are pre lubed prior to starting the first time by spinning the oil pump. Many new engines have crank mounted g rotor oil pumps meaning that you need to spin the crank to build oil pressure. Spin the oil pump with the crank stationary if you can and if you want, but using a quality assembly lube and having the parts and internal oil lines absolutely clean is a better way to engine start up success.