If you could filter out the blow-by in a conventional engine, would synthetic oil last for 25,000+ miles?

That is, if it were feasible to have a separate ';circuit'; for the air in the crankcase to be aggressively exhausted and replaced with fresh ambient air, assuming it's the blow-by being absorbed by the oil that causes the synthetic oils to break down, not the heat in the crankcase or the heat on the cylinder walls. The combustion by-products in blow-by are readily soluble in the synthetic and conventional oils.If you could filter out the blow-by in a conventional engine, would synthetic oil last for 25,000+ miles?
There is very little blow-by in modern engines. There are too many laws about polluting. A good synthetic. like ELF or Amzoil or Mobil One, creates NO sludge and gives off very little vapor. The oil vapors are supposed to be burned up through the PCV (positive crankcase ventilation) system. If an engine, weened on lousy regular oil, is de-sludged with butyl cello-solve and most deposits are removed, fresh synthetic oil can last for 25,000 miles or a year and a half. But this depends upon distances driven between start-ups. My Audi's lasted even longer between oil changes.If you could filter out the blow-by in a conventional engine, would synthetic oil last for 25,000+ miles?
Acids break down the oil, and acids are part of the combustion process. The air being ingested has a certain water content and that water usually ends up in the oil and helps to form the acids. The blow by of an engine in good operating condition is negligible. There used to be a device called a Franz oil filter that would allow you to run 10 k miles on regular petroleum based oil. So it is my belief that superior filtration and water absorption are the keys to oil longevity, no matter what type.