My mechanic probably thinks I'm neglecting my car, but if the oil analysis says it's fine, why fix what isn't broken? Longer intervals can save a TON of cash over time, which is a HUGE plus. It also means less used oil to dispose of, so it's better for the planet. The KEY is using good oil and actually checking it, not just guessing. I've pushed my changes to 10,000 miles with synthetic, and the engine runs like new. Trusting the oil's condition over a calendar is just SMART maintenance.