You have a good idea for a T-shirt "Trust me, I
'm an engineer work at "
Could you elaborate relevance of video you shared regarding oil "science"?
You could watch the videos
Regarding the first one about oil "science" I hear people saying (and "teaching") to others wrong things. It's common (at least for me) for example to hear that a 10W40 oil is an oil for 10k km oil changes and that a 5W40 oil is an oil for 15k km oil changes and with 5w30 you change your oil every 20k km. As I am sure that you know, this is totally wrong. What defines the service intervals is the engine and the manufacturer, not the type of oil used. A manufactures specifies some norms for the oil (507.00 in your case I guess) and a range of viscosities. In the most recent ones, its only one I think, 0W20. As owner you only need to fullfil these two things.
Regarding the second video, if you have time, explore some videos of him. They are very interesting, at least if you're into cars, engineering and motorsport. When he bought the car, it had 180k km and the timing belt has never been serviced before! It was supposed to be done at 120k km... The engine was not in best condition, after the timing belt was changed, the engine was much more smoother. Here you can see some form of overengineering because the belt didn't snap at 121k km.
But of course that for manufacturers price counts a lot. Sometimes decisions aren't made by engineers, they are made my managers, In modern VWs I hate to have "fluffy" door cards at the front and hard plastics at the back. I also find unacceptable that the Mk8 Golf lost the gas strut in the bonnet (introduced in the Mk4 Typ 1J) and that the glove box had a textile lining removed to be all plastic... But I guess that focus groups showed them (apparently) that owners don't care or even don't know the differences, so managers have a way to cut costs.
I prefer to focus more on the technical side of things
Feel free to share info which engine you have, which oil you prefer and how many miles you usually manage on your variable interval
It't not my car, but I have access to a 98 Passat 1.9 TDI with 245k km... Castrol Edge 5W40 with norms 505.00/505.01. With this engine there is no LL available, only the 15k/1y fixed interval and the oil is changed after 1 year because it only makes around 5k km per year.