If the Aussies were 'invincible' once, it was because they had in their mix, possibly the best 'keeper-batsman to have played the game. I don't think it's easy to predict anything about Test cricket at the moment. I think they're possibly just losing the big 50-50 moments in Tests recently. I think they're just trying to focus on getting their cricket right and not worrying too much about the verbal side of it. I don't think there's any real philosophy on sledging.
Source: Times of India November 10, 2016 11:28 UTC