Good stuff! Interestingly, the trend toward thinner oils seems like a return to me. Many cars used to specify SAE 20 oil when ambient temps were between freezing and 100°F or so, so they must have thought it was adequate when the engine was up to operating temp.
VW in particular spec'd SAE 20 until about 1966, and oil temps were a little higher in those engines compared to water-cooled engines of the day. It seems that in the time since, there was a trend toward thicker and thicker oils in the belief that they provided more cushioning for the bearings, especially in hotter-running engines. So you'd see SAE 30, 40, 50, even 60.
It's good to see that sense has returned! Start-up wear is what we should be concerned with, and as long as the oil pump can maintain adequate pressure, and the oil has adequate anti-scuffing additives, why not go thinner?
In fact, aircooled VW fans often cause themselves a lot of trouble with thick oil, because the extra pressure causes oil to bypass the cooler, and it runs hotter as a result.
There was a guy on BITOG that ran his otherwise-stock Jeep on 0W10 and still got great wear numbers.
BTW,
Ecky, you might want to trim your quote back to a couple sentences. I think copyright laws usually allow for quoted summaries, but frown on reproducing whole pieces.