that's TRUE, but when your base division(VW) isnt up to par, more than likely your higher end will suffer too.
This is also true, but there are some exceptions to this rule. Porsche is also a division of the VW group, however Porsche is one of most reliable European/German automobile brands today.
But in essence, your theory is spot on & exactly the main reason as to why Audi's overall reliability stinks.