If I had to ditch one person in the Proteas' setup, it would be AD. I have never known a team that gets its lengths wrong so constantly.
Remember the CT in England, where we pitched up with a plan to bowl short against India "because their batsmen can't play the short stuff"? Shikhar Dhawan murdered us. And yet, for fifty overs, we persisted with the same useless game plan.
Remember the first Test v Pak in UAE? We went head-hunting and they trounced us. AD had to come home, Vincent Barnes took his place, the bowlers bowled much fuller for the second Test and we won by an innings.
Remember the first Test v India at the Wanderers? We decide to bowl back-of-a-length away-swingers because "India's batsmen will nick off". Except they didn't. They just shouldered arms and let it go through. Virat Kohli scores a ton and our bowlers exhaust themselves by bowling a completely ineffective line/length. AD and Biff should have seen by lunch on day one that it wasn't working and turned to Plan B. Yet they persisted with it the entire day.
When AD coaches in the IPL, you just know his team will go for 9 an over. He was a legendary player, one of the best ever. But playing and coaching are not the same thing. We often get our lines and lengths wrong, we often bowl with poor discipline (no-balls, etc), and we seemingly have a policy to not bowl yorkers. We need to eliminate all three. I'm not sure AD is the guy to do that. In fact, I suspect he's the reason it happens.