The test against the Argentinians are coming up - so what next

The Springboks have to play the Argentinian test on 8 August 2015 and that brings to the fore some interesting questions.  
One of those questions are about scrumming.  In the tests against last year the Springboks were seriously embarrassed.   The Springbok scrumming collapsed completely - that is a fact.  
So what happened in the two tests this year.  In the Aussie test and yesterday the scrums was static.  The real norm would be what did the Argentine scrum do to the Aussies yesterday?   The only place where they did make life difficult for the Aussies was in scrumming.  So what are we learning from last year and the two tests mentioned?
Jannie du Plessis got praised like it  is unbelievable for his performances - but was his scrumming really as good as the praise-singers claim.  I saw stagnant scrums at best on the part of Jannie and Beast in both tests - nothing special.  The only really good scrum last week was when Malherbe replaced Jannie in the first half.  The other issue was that scrumming became better significantly after Matfield left the field last week.
So what is to be learned from our experience last year and in the last two tests?  I would say that it would be a disaster in scrumming if Jannie is retained in the next test and if Matfield is selected at lock.   If that happens it would have a serious       negative impact on the performance of the Springboks in that test.