There are basically three post-December 2017 scenarios.
The first is a Dlamini-Zuma victory (“NDZ”), after which the ANC will probably split - and struggle to secure 50% at the polls in 2019. Following which, corruption will persist and economic growth will remain low.
The second is a Ramaphosa victory (“CR17”), after which the ANC could split, but probably not - and where getting 50% at the ballot box could be a little easier. Further, corruption will be tackled and the economy will slowly improve.
The third is the “unity scenario”, whereby there will be either a loser Deputy President and the ANC will paper over the cracks (and struggle at the ballot box), or a compromise candidate may be elected as President, with new possibilities for anti-corruption initiatives, as well as the economy.