Rained ruined second half of the day's play.
With Australa 7 for 494 and 3 days left, just a matter of whether Clarke wants to bat on or put South Africa in already.
Personally I think he needs to have a discussion with bowlers first to see if they are keen for him to enforce follow on, therefore committing them to a long time out in field for 2 South African innings to get the 20 wickets.
If they say they are up to it, then Aussies should bat on and get probably another 70 to 100 runs if possible or bowled out, thereby giving them better chance of bowling South Africa cheap enough to be able to force follow on.
Lets say they got to 570, it then gives us some room to possibly bowl South Africa out for 370 or less in 1st innings, thereby have better chance of enforcing a follow on and still having back up 2nd innings if we needed it at all.
If we declared right now and South Africa made just over 300 in 1st innings then we lose ability to enforce follow on. Score a few more runs though before declaring and we got better chance of ability to bring follow on, into the game.
Clearly getting 20 wickets is 1st priority but you've got to access the wicket and get a feel first for realistic 1st innings score as par for 1st innings.
Given scores from our innings, you got to expect par score for South Africa is over 300 in 1st innings. Hence why I think why we should bat on a little more in morning to get our score a little higher in as quick time as possible.