This came from the early days BEFORE the air cleaner was ducted with cooler air. On an older car that just had a snout off the cleaner this greatly improved the amount of air going into the engine and also made it sound great.

Flipping the air filter cover? I would guess most haver never heard of this, given the modern air box designs don't allow for this.

I hope so - it's hard to believe we still use rubber air-filled donuts for 100% of our grip. Although I have no idea what would replace them.

I share your family's hate of VWs. After owning a Jetta and having it work approximately 50% of the time during my entire ownership of the thing, I swore off VWs for all time. Being that much of it could not be serviced by non-VW mechanics, I was often at the mercy of my local crooked VW dealership.

1) That sucks about the Tiguan.