I'm in.

Basically this system could be simplified by returning the companion ticket received with other awards issued by the companion for the main traveller.

It would reduce the miles required for each party if the savings is shared. Say, I was booking ZRH-JNB and back in first - instead of 140'000 miles I would pay 210'000 miles, but the companion would owe me awards of 105'000 from his account. The two trading partners could even negotiate who adapts their schedule to accomodate the other one, maybe in return for a different ratio.