@chilehed Going from 0W20 to 0W30 is not to lower the pour point or "borderline pumping ", it is to ensure that we have good film strength at high speed and higher opertiong loads and temperatures.
Looking through the lubricant's handbook of a popular major oil company, I find for their synthetic oils, the borderline pumping virtually the same for the 0W20 and 0W30. The 0W30 has a slightly higher Viscosity Index at 172, vs 169 for the 0W30. This same company's regular mineral oils have a Viscosity Index of 155 for the 5W20 and 159 for the 5W30.
I agree that more engines are destroyed in the US through racing a very cold engine than by driving fast across the Mohave desert in the summer. Most of Europe is a lot milder than the US, and fast driving dictates heavier oils like 0W40 synthetic.
The 0W30 synthetic cover a wide range of operating conditions resulting in maximum engine life. I have been using this type oil for a long time and have never disposed of a car because the engine was worn out. We keep our cars 15 to 20 years.
A friend tows a heavy trailer to Florida each year from the cold North. He uses 15W40 mineral oil in his F-150 and uses an engine block heater for safe and easy starts in the North. He could use a 5W40 synthetic as well, but does not want to spend the money.