Some folks have little idea how good modern Engine Oils have actually become even in the last 10yrs.
The Oil in our Cars more so the TDI's id say over the petrols esp these VAG engined cars
is so advanced it can do upto 21,000 miles without it needing changed.
Now its upto each & every one of us to decide if thats ok but eitherway VW Group are happy
enough otherwise why do they have these extended variable service intervals?
So i opted to change mine every 10,000 miles but still using the same silly GARAGE charged
Long life Spec Factory OIL OK.
I never used a drop from 4500miles it had on when i bought it until it was changed at just over 10,000 & hey presto dipped it this morning & its bang-on the top mark.
Your correct oil technology has advanced in considerably in the last 10 years, but so has engine design and modern engines can be much harder on the oil especially with all the extra emission control systems and the quest to meet ever tighter exhaust emissions.
Take you statement about your car using no oil, how do you know it hasn't , one of the byproducts of the dpf and the regen system is that heavy oil (diesel fuel) is washed past the rings and into the sump during a dpf regenerating cycle.
So you could in fact be using oil and it's simply being replaced with diesel, giving the illusion that you have used no oil.
As for vag being happy to have extended or variable oil change, that's more to do with vag keeping fleet buyers happy, as they are one of biggest buyers of new cars and as they only tend to keep them 3 years so they couldn't care less what happens 10 years down the line, they just want vehicles on the road earning money and in the garage being serviced as little as possible. Plus they tend to do mostly high miles motorway which is probably least stressful on the oil of any driving scenario.
I'm with Kazand, I'd bung the tractor garage a few quid and change the oil every year,it's cheap peace of mind