Another contentious area is the refereeing of the advantage. It seems to be accepted practice now that knock on advantage expires if the non-offending team either kicks the ball, passes through the hands or makes a few metres through pick and drives. And I am happy with those calls in the main.
So, what happened with Walsh not calling advantage over after the Brumbies knocked on and the chiefs kicked through, finding touch about 15 - 20 m advanced towards the try line. Play was called back for the scrum, Chiefs feed, when it probably should have been a lineout with Brumbies throw in. This occurred with around 4 minutes left to play, and allowed the Chiefs to advance play to within 5m of the try line where the subsequent lineout resulted in the questionable knock on decision that then led to the winning penalty for the Chiefs.
Conceivably, had advantage been nullified when the Brumbies knocked on previously, they would have retained possession about 25m out from their try line, and the result could have been entirely different.