So, the very fine VTEC screens block oil flow if the oil is too thick?
Does it also "stand to reason" that "drastically thicker" oil on start up will also cause "issues"?
Room temperature 0W20, not even cold, but room temperature, 0W20, is far thicker than a XW40 at operating temperature.
So, if the "drastically thicker" 40 causes issues, then the 0W20 will cause a lot more issues until the oil warms up.
Alternatively, there may be no problem at all from XW40 oil, since oil during warm up is much thicker.