A preoiler system would be easy for car manufactures to install at the factories. With fuel injection, when you turn the key on, the fuel pump immediately pressurizes the fuel sys. So the exact same thing could be done for oil. Not that I am an engineer, but I figure you could place an external pump on the engine with a line going into the oilpan and one going to the valve train. When you turn the key, it draws oil from the pan, sends it to the valve train and as soon as the engine is running for a few seconds, the electric oil pump turns off. I say valve train because that's where most of the where is with cold starts.
You have to remember that there is a vested interest from both the auto and oil industry to not have something like this on all cars. As for the oil industry, the big push for synthetics is it's ability to get to the top of your engine when cold, which a pre-oiler would take care of. For the auto industry, this type of device would probably make engines last even longer, therefore you may not buy another car for a long time.

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1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member