Shiggins I examined 2 games in depth. Overall, there was no significant difference between the Wallabies and All Blacks in their slowing of the ball when defending tackles / rucks. I'm not about to do another 10 to make the data more, or less, significant, as I don't have time.
If you want to look at any one game, you will always find a sequence of play, or series of rucks that show repeated "offences", and drawing that out to prove an enduring behavioural pattern is a long stretch. For example, the video at the end of my blog article showed a series of 5 breakdowns in one game where the All Blacks had defending players slow-ish to clear the tackle area. Not all were penalisable, but eventually they did concede a penalty. I saw no other sequences suggesting a programmed pattern, nor was there a clear difference in where the penalties were conceded on the field, although the All Blacks were slightly more likely to concede one in the "red-zone", while the Wallabies were slightly worse overall. Maybe the Wallabies try to slow it as much as anyone, but are less good at it?
I learned one thing - watch both teams over time with the same eye, and it is illuminating. As fans we all tend to howl at the opposition, as do I when games are on, but the cold light of day can reveal a broader landscape.