Thank you @42pilot for taking the time to explain at length. If I understand and have simplified this correctly, a small amount of oil burn (not loss/leak) is a byproduct of using better performing metal alloys for each specific component, which in aggregate produce more power/efficiency, but they expand and contract at different rates under temperatures due to the differences in their composition, and some oil enters the cylinders through the piston heads.
Until you correct me I deduce:
- The oil burned produces slightly more emissions but still maintains their level low enough to comply with standards
- The burned oil may actually help prolong the life of some components as it provides additional lubrications
- The burned oil may reduce the life of some emission equipment (catalytic converter, for instance)
- If one experiences this from the time the engine is young, it is indicative of the design byproduct. If one approaches this at over 50k miles / 80k km, then it is not due to design, but wear/tear/leaks/bad rings/other issues.
- This is more likely to occur in high-performance engine that operate at higher pressures, with a high red line. And therefore, this should not occur in low pressure engines. And, diesels that have pressurized fuel/air mixtures but not have highly pressurized cylinders, have lower redlines, and rely on the fuel to deliver lubrication.
- Keep a an extra liter/quart of the appropriate oil handy in the garage
Thank you again.