One word, politics.

Audi is Piech's baby, of course Audi wants everything, Piech probably want to have Porsche under Audi's umbrella if he has his way just to rub dirt on Porsche's family's faces.

Look at how confused the whole VW line up is, overlap products and brands everywhere.

All because Piech wants his baby Audi to be everywhere up and down market, left and right into niches that the VAG already has their hands on with other brands within the company.

Thank god common sense won with Porsche doing the sports car leaving Audi on the sedans.

I don't mind Audi doing the SUV, actually I don't mind seeing the Cayenne disappeared leaving only sports cars and a future sporty sedan aka Panamera left in Porsche. WIth Porsche living under the VAG house it doesn't need to money from Cayenne sales to finance their sports car program.

R8 should die, it takes away from Porsche's market share, they already have the Lambo Gallardo in the house, and the R8 is nothing more than a rebadged cheapen version.

Halo car -> Bugatti

High end sedan/Limo -> Bentley

High end exotic -> Lambo

High end sports car -> Porsche (with a sporty sedan version of the A8 tuned by Porsche)

Luxury and mainstream sedan, coupe, SUV -> Audi aka BMW fighter

Cheap people movers battling the Japanese -> VW (back to it's roots), no more $50k VW.

Cheaper still battling Koreans -> Seat and whatever Eastern European brand VAG has.

Virtually no overlap on products, every sale is fresh money from the market, no more taken money from one division to the other.

Porsche do the sports car prototype racing, it has far more heritage doing that than Audi.

Rally/off road goes to Audi, yes Audi has a bunch of Le Mans wins, but there is really no sports car racing heritage, it's only been a a little more than a decade that Audi is successful. Audi is far more famous for rallying with it's Quattro brand.

F1 racing, natural choice is Lambo, who competes directly against Ferrari with their cars, racing them is what comes next.

Another option is to scrap the Audi name and go back to Auto Union, and race with that name.