Did anybody watch the Boks vs Argies?
Yet another technically perfect decision at the end, which made no sense in reality. Look at from 2:58 in the video.
Basically, Argentina scored a match winning try, which the ref then went back to the TMO for something in the prior phase which didn't really have an effect (outside of the sliding doors theory) on the try being scored.
Surely, common sense states that for an obstruction, which happened right in front of the AR and Ref, if they can't call it at the time, then its' not clear enough.
FWIW I reckon the SA player milked it for all it's worth.