South Africa to LHR confusion

[turtlemichael]

I'm looking at an AA award flight from JNB to LHR in J. It won't be for more than 12 months so I'm at the early planning stage. On the dates I've looked at AA offers me BA JNB-CPT-LHR in J and a direct flight JNB-LHR in Y. In J there is a 20 hour connection in CPT. That's less than convenient so I had a look at departing from CPT. Now AA offers me CPT-JNB-LHR on the same day in J with a 20 hour connection in JNB. The Y flight is again direct CPT-LHR.

Am I missing something or is this really just designed to devalue the Milesaver awards? Only milesavers are available.